science fora 

USGS

changing world

Co-RICH Fe-Mn CRUSTS FROM THE MARSHALL ISLANDS 

(LEG 1) AND HYDROTHERMAL AND HYDROGENETIC FeMn DEPOSITS FROM MICRONESIA (LEG 2), KODOS 98-3 

CRUISE, WEST PACIFIC

By

James R. Hein1 , Jai-Woon Moon2, Kyeong-Yong Lee2, Jennifer S. Bowling1 , KiHyune Kirn2, Malia Burrows 1 , Sung Hyun Park2, Youn-ji Choi2, Anthony A. 

Schuetze1 , Hoi Soo Jung2, Hyun-Sub Kim2, Gun Chang Lee2, Cheong-Kee 

Park2, Seung Kyu Son2, and Chan Young Park2

Open-File Report 99-412

1999

This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey 

editorial standards or with the North American Stratigraphic Code. Any use of trade, product, or 

firm names is for descriptive purposes only and does not imply endorsement by the U.S. 

Government

!U.S. Geological Survey, 345 Middlefield Rd., MS 999, Menlo Park, CA, 94025, USA

2Korea Ocean Research and Development Institute, P.O. Box 29, Ansan, 425-6000, Seoul, Korea
INTRODUCTION

The KODOS 98-3 cruise took place 13-28 August 1998 aboard the R.V. Onnuri and was 

divided into two legs. Leg 1 operations included mapping and sampling Litakpooki Ridge and 

mapping Lomilik Seamount, both within the Exclusive Economic Zone (EEZ) of the Republic of 

the Marshall Islands (RMI) (Figs. 1-3). Leg 2 operations included mapping and sampling a 

corridor of the Yap convergent margin (YCM) extending from the southwestern margin of the 

West Caroline Ridge west to the Yap back-arc region in the EEZ of the Federated States of 

Micronesia (FSM) (Figs. 4, 5). Members of the KODOS 98-3 cruise (Table 1) participated in this 

second cruise of a renewed effort by the Korea Ocean Research and Development Institute 

(KORDI) and the U.S. Geological Survey (USGS) to study seamount mineral deposits. Earlier 

efforts included three USGS-KORDI cooperative cruises aboard the R.V. Farnella, one each in the 

years 1989-1991, and more recently cruise KODOS 97-4 in 1997.

The first set of objectives of the KODOS 98-3 cruise was to map the distribution of thick 

ferromanganese oxyhydroxide crusts (Fe-Mn crusts) on Lomilik Seamount and Litakpooki Ridge 

and to determine the geologic and oceanographic conditions that promoted growth of thick Fe-Mn 

crusts. Reconnaissance sampling and mapping of Lomilik Seamount were completed in 1989 

during the first cooperative USGS-KORDI cruise aboard the R.V. Farnella (F10-89-CP; Hein, 

Kang, et al., 1990) and both Lomilik and Litakpooki were studied during the KODOS 97-4 cruise 

(Hein, Moon, et al., 1998). Lomilik was chosen for detailed work because during the 1989 

cruise, the thickest (180 mm) shallow-water Fe-Mn crust ever recovered from the ocean basins 

was collected from its summit; thick Fe-Mn crusts (up to 130 mm) were also collected in 1997. 

Thick Fe-Mn crusts up to 154 mm thick were collected on Litakpooki Ridge during cruise KODOS 

98-3, which are described here.

The second set of objectives of the KODOS 98-3 cruise was sampling and mapping of the 

YCM. Reconnaissance sampling and mapping of that region was completed in 1990 and 1991 

during the second and third cooperative USGS-KORDI cruises (F11-90-CP and F7-91-WP) 

aboard the R.V. Farnella (Hein, Ahn, et al., 1992). During the 1990 cruise, hydrothermal 

stratabound Mn-oxide deposits were recovered from the crest of Yap arc, along with 

hydrothermally altered rocks, serpentinite, blue-serpentinite muds, and abundant vein quartz. 

Additional hydrothermal deposits were collected during leg 2 of KODOS 98-3.

Representative Fe-Mn crust samples, hydrothermal stratabound Mn oxides, and substrate rock 

samples from the dredge hauls taken from those areas during KODOS 98-3 were analyzed for this 

study, which extends our previous work on Fe-Mn crusts collected in and around RMI and FSM 

(Hein et al., 1988; Hein, Kang, et al., 1990; Hein, Ahn, et al., 1992; Hein et al., 1997a; Hein, 

Moon, et al., 1998). This report presents data for all dredge hauls, including sample descriptions, 

detailed chemical (major, minor, platinum group, and rare earth elements) and mineralogical 

analyses of bulk Fe-Mn crusts, individual crust layers, hydrothermal Mn, and substrate rocks 

collected during KODOS 98-3. Correlation coefficients and Q-mode factor analysis are used to 

determine relationships between and among elements and associations of elements with 

mineralogical phases.

Shipboard Operations

Shipboard operations on Litakpooki Ridge included four dredge hauls, two piston cores, two 

CTD casts, and 534 km of SeaBeam bathymetric lines including 152 km of 12-channel airgun lines 

(Tables 2-5; Figs. 1-3). Operations on Lomilik Seamount included 279 km of SeaBeam 

bathymetric lines. Operations on the YCM included five dredge hauls, two piston cores, two box 

cores, two multiple cores, nine CTD casts, one deep-sea camera-video survey, and 737 km of 

SeaBeam bathymetric lines and 12-channel airgun lines (Tables 2-5; Figs. 4-5). Of the nine dredge 

hauls attempted, six provided usable samples, one contained mostly pumice, and two had no 

recovery (Tables 5, 6).
Bathymetry and Seafloor Descriptions

Litakpooki Ridge is located at the southwestern margin of the RMIEEZ (Fig. 1). The 

bathymetry of the central part of the ridge shows a relatively flat top at 2000-2800 m water depth 

dotted with small hills that rise as shallow as about 1600 m depth (Fig. 2). The ridge summit 

narrows and extends to the northeast to the edge of the survey area. A rift zone is defined by a 

ridge that extends to the northwest from the summit. The base of the Litakpooki ridge is at about 

5000 m water depth. Channels characterize the very steep northern slope. Slope angles on the 

summit are mostly less than 5°, whereas those on the flanks are up to 30°, with an average slope 

angle of about 11° (KODOS, 1999a).

Foraminiferal sediment fills some lows and forms a thin blanket over the central and northeast 

parts of the summit where dredges D3 and D4 encountered only sediments (Fig. 2). Seismicreflection profiles (KODOS, 1999a) show that much of the summit is underlain by sedimentary 

rocks, with protruding volcanic hills composed of basalt. Dredges Dl and D2 and dredges D14 

and D15 from KODOS 97-4 (Hein, Moon, et al., 1998) show that those sedimentary rocks consist 

of bioclastic and foraminiferal limestones, breccia composed of mostly volcanic and phosphorite 

clasts in a carbonate fluorapatite cement, phosphorite, and minor ironstone. Most thick crusts were 

collected from saddles between summit hills.

Lomilik Seamount is located among a large group of seamounts to the west of Anewetak Atoll 

in the western Marshall Islands. The bathymetry reveals a flat-topped edifice with a summit at 

about 1500 m water depth and small hills rising to about 1350 m (Fig. 3). A broad, gently sloping 

summit terrace occurs on the NE flank down to about 2400 m which steepens in slope on the SE 

flank, but does not exist on the north, west, and south flanks. The terrace is separated from the 

summit by a 200-250 m-high scarp. Many volcanic pinnacles occur on the east, southeast, and 

west flanks of the seamount (Fig. 3). Lomilik Seamount is connected to Lami Seamount (Fig. 1) 

by a ridge on its NW flank (Fig. 3). A large landslide likely created the notch in the south flank 

which begins where the summit narrows before changing trend to the northwest along the ridge 

that connects with Lami Seamount. The seamount base is at about 4600 m water depth. The 

summit region slopes at less than 5° and the flanks up to 20°, with an average slope of Lomilik of 

about 11° (KODOS, 1999a).

The terrace and summit support a thin blanket of foraminiferal ooze between outcrops of basalt, 

volcaniclastic rocks, and foraminiferal and bioclastic limestones (Hein, Moon, et al., 1998). Most 

thick crusts were collected from the terrace and the scarp that separates the terrace from the summit, 

whereas the thinnest crusts were collected from the middle and upper steep flanks of the seamount; 

the lowermost flanks were not sampled.

YCM bathymetry from east to west is characterized by a gently dipping summit of the 

southwestern margin of West Caroline Ridge at about 1500-2200 m water depth (Fig. 5). West 

from the summit, the outer trench slope is characterized by an upper steep wall; rough, central 

ridge and valley topography; and a lower steep, irregular slope showing block faulting that bottoms 

at about 8600 m. The trench axis deepens to the south. The inner trench wall is more uniform in 

topography than the outer trench wall and rises through a series of thrust faults to a summit ridge at 

about 1500 m. A summit seamount shallows to about 500 m water depth (Fig. 5). Most sampling 

was completed on the west side of the summit ridge in the back-arc area at water depths of 1750- 

2800 m. Seismic-reflection profiles (KODOS, 1999b) show that most of the region supports thin 

sediment cover, with basement highs cropping out in the arc and back-arc regions.

CTD Data

Water temperatures measured in CTD-1 (Litakpooki Ridge; Fig. 2) and CTD-2 (open-ocean 

between Litakpooki Ridge and Lomilik Seamount; Fig. 1) profiles range from 2.2° to 29.2° C and 

salinities from 34.4 to 34.9 psu, defining high temperature and low salinity surface waters and a 

seasonal thermocline at about 100 m water depth (KODOS, 1999a). Dissolved oxygen contents 

range from 1.3 to 4.3 ml/1, with maximum values occurring at about 100 m water depth and 

minimum values at about 300 m (Table 4). The depth to the top of the oxygen-minimum zone
(OMZ) is about the same (280 and 275 m), although the depth to the lowest oxygen content is 36 

m deeper at the more northerly site. The 5° and 10° isotherms are also deeper at the more northerly 

site (Table 4).

Nine CTD profiles were taken at the YCM, where the lowest oxygen content at each site is very 

uniform at 2.0Q±0.08 ml/1. These values show that primary productivity in surface waters is not 

as high in this region as in the western RMI, where minimum values are 1.3 ml/1, indicating greater 

amounts of oxygen consumption during degradation of organic matter. Indications of 

hydrothermal activity were not seen in water column properties at any of the sites.

METHODS

X-ray diffraction was completed on a Philips diffractometer using Cuka radiation and a 

curved-crystal carbon monochromator. Abundances of the 10 major oxides and Cr, Ba, Sr, Y, Zr, 

Nb, and Rb in substrate rocks were determined by X-ray fluorescence spectroscopy (XRF; 

Taggart et al., 1987); Fe(II) by colorimetric titration (Peck, 1964); CO2 by coulometric titration

(Engleman et al., 1985); H2O+ by water evolved at 925°C as determined coulometrically by KarlFischer titration (Jackson et al., 1987); E^O by sample weight difference at 110°C for greater than 

one hour (Shapiro, 1975); F and Cl by specific ion electrode, S by combustion and infrared 

spectroscopy (Jackson et al., 1987), and C by induction furnace; Y, U, Th, and rare earth elements 

(REEs) by inductively coupled plasma-atomic emission spectrometry-mass spectrometry (ICP-MS; 

Aruscavage et al., 1989; Lichte et al., 1987a,b); and Au, As, Sb, and W by neutron activation 

analysis (NAA; McKown and Millard, 1987). Low totals for the phosphorite sample occurs 

because of typically high F, Cl, and S contents, which are not included in the total.

For Fe-Mn crusts and hydrothermal stratabound Mn, the concentrations of Mn, Fe, Si, Al, 

Mg, Ca, Na, K, Ti, P, Ba, Nb, Rb, Zr, and Y were determined by XRF; Be, B, Co, Cu, Ge, Li, 

Mo, Ni, Pb, Sc, Sr, V, Zn, and Ag were determined by ICP; Bi, Cd, Ga, In, Sn, Tl, Y, Au, 

REEs, and platinum group elements (PGEs) by ICP-MS; As, Au, Br, Cr, Cs, Hf, Sb, Se, Ta, Th, 

U, and W by NAA; Te by graphite furnace atomic-absorption spectroscopy; Hg by wet chemical 

techniques; S by combustion and infrared spectroscopy; and Cl by specific ion electrode. REEs in 

plots are normalized to both chondrites (Anders and Grevesse, 1989) and shale (PAAS, PostArchean Australian Shale; McLennan, 1989).

The usual Pearson product moment correlation coefficient was used to calculate the correlation 

coefficient matrices. For Q-mode factor analysis, each variable percentage was scaled to the 

percent of the maximum value before the values were row normalized and the cosine theta 

coefficients calculated. The factors were derived from orthogonal rotations of the principal 

component eigenvectors using the Varimax method (Klovan and Imbrie, 1971). Communalities 

for all samples are >0.97.

Growth rates of non-phosphatized crusts were determined using the empirical equations of 

Puteanus and Halbach (1988): GR = 1.28/Co-0.24, with cobalt content in weight percent; and 

Manheim and Lane-Bostwick (1988): Co" = Co-0.0012%, GR = 0.68/(Con) 1>f7 .

LITAKPOOKI RIDGE SUBSTRATE ROCKS 

Descriptions

Substrate rocks based on dredges Dl and D2 as well as dredges D14 and D15 from KODOS 

97-4, in decreasing order of abundance include limestone, breccia, phosphorite, basalt, and 

ironstone (Tables 5, 6; Hein, Moon, et al., 1998). As seen in hand samples, most limestones from 

KODOS 98-3 Litakpooki dredges are either friable to well-lithified foraminiferal limestone or 

bioclastic limestone composed of shell hash and foraminifera. Limestones are pale-brown to offwhite, yellow-brown, or brown. They are commonly peppered with Fe-Mn oxyhydroxide grains,
contain Mn dendrites, or have vugs lined with Fe-Mn oxyhydroxides. Some limestone samples 

are partly phosphatized, which grade into phosphorites. Phosphorites are massive, vuggy, or 

pebbly. Pebbly phosphorite contains sparse, brown basalt clasts commonly coated with Fe-Mn 

oxyhydroxides, and yellow-green altered hyaloclastite clasts. Vugs in vuggy phosphorites are 

lined with Mn oxides. Carbonate fluorapatite (CFA) veins and Mn-oxide dendrites are common in 

all three types. Most of the phosphorite is CFA-replaced limestone, more rarely CFA-replaced 

basalt.

Breccias most commonly consist of white to brown phosphorite, brown basalt, and brown 

ironstone clasts in cream to pinkish CFA cement, rarely Fe-Mn oxyhydroxide cement. CFA veins 

are common and Fe-Mn oxyhydroxide veins also occur. Volcanogenic clasts are commonly partly 

to completely replaced by smectite. Basalt is altered, brown to red-brown, and may be laced with 

CFA and Fe-Mn oxyhydroxides and contain large yellow-green amygdules. Sample D2-2E 

consists solely of smectite, yet maintains relict volcanic textures.

Ironstone samples are brown to dark brown, massive, and dense. Ironstone also occurs as 

clasts in breccia and pebbly limestone and formed by replacement of basalt. Ironstone most likely 

formed from hydrothermal processes related to formation of the volcanic edifice during the 

Cretaceous (Hein et al., 1994).

X-ray Diffraction Mineralogy

For the four samples for which minerals were identified by X-ray diffraction, primary 

volcanogenic and sedimentary minerals include plagioclase and calcite; and secondary minerals 

include CFA and smectite (Table 7). Secondary CFA is the most abundant mineral in these 

samples and occurs in three of the four samples as a major or moderate constituent, regardless of 

rock type (Table 7).

Fresh basalt was not recovered in dredges Dl and D2. Altered basalt consists of plagioclase 

and various amounts (up to 100%) of smectite and CFA. The most altered basalts lack all primary 

minerals, but maintain volcanic textures. CFA replaces basalt and fills vesicles and fractures.

Limestones are composed chiefly of calcite, with various amounts of CFA, showing all 

gradations from limestone (only calcite) to phosphorite (only CFA). Most phosphorites have relict 

limestone textures, especially that of foraminiferal sand.

Chemistry

The most P2Os rich CFA-replaced sedimentary rock has a CaO^Os ratio of 1.63 (Table 8), 

whereas theoretical compositions for CFA produce ratios that range from 1.5 to 1.6 (Manheim and 

Gulbrandsen, 1979). The very slight excess Ca over P in some KODOS 98-3 samples may be due 

to additional Ca associated with minor contamination by volcanogenic plagioclase, phillipsite 

cement (an alteration product of volcanic debris), or to relict calcite in the phosphatized limestone. 

However, Hein, Moon, et al. (1998) showed that, CaO^Os ratios between 1.60 and 1.66 

characterize chemically very pure phosphorites, indicating that CaO/P2O5 ratios between 1.58 and 

1.66 are characteristic of uncontaminated marine CFA. Ratios in that range have been found in 

many of our previous studies (e.g., Hein, Kang, et al., 1990; Hein, Ahn, et al., 1992; Hein et al., 

1993). The CaO^Os ratio of 1.63 is very near the most cation- and anion-substituted francolite 

(1.62) end of the fluorapatite (1.32)-CFA range (Manheim and Gulbrandsen, 1979; McClellan and 

van Kauwenbergh, 1990). The Sr content for the phosphorite sample is 1260 ppm, near the 

middle of the range (900-1600 ppm) found for other central Pacific phosphorite samples (Hein et 

al., 1993). Normalized REE plots of phosphatic limestone (Table 9) show a seawater-type pattern 

with large negative Ce anomaly, small positive Gd anomaly, and heavy REE enrichment (Fig. 6). 

These identical patterns indicate that the CFA as well as the calcite were derived from seawater.

Smectite occurs in major to moderate amounts in two of the four samples analyzed, and is 

especially abundant in the strongly altered basalts. The pure smectite sample (D2-2E) has relatively
high Si, Al, Fe, and Zr contents and low Mg content, indicative of an iron-rich montmorillonite 

(Tables 7, 8).

Most samples of basalt and basalt clasts in breccia are altered to smectite and goethite and are 

rarely replaced by phosphorite and phillipsite. Alteration is best characterized by increases in 

Fe2O3 and water and decreases in FeO and K2O contents (Table 8). Volcaniclastic mudstone and 

hyaloclastite have compositions comparable to highly altered basalts.

SOUTHWEST CAROLINE RIDGE SUBSTRATE ROCKS

Dredge D7 was taken on southwest Caroline Ridge and consists of pillow basalt wedges, 

limestone, and breccia in that order of abundance (Table 6). The basalt is gray (relatively fresh) to 

brown (altered), massive, and variably vesicular with a red-brown alteration rind underlain by a 

black basaltic glass rind. Small vesicles occur in the basalt below the glass rind, which grades into 

massive basalt. The basalt is composed of primary plagioclase, pyroxene, magnetite, and 

secondary smectite and hematite.

Foraminiferal limestone is white, friable, massive, and one sample contains a gray volcanic ash 

layer. The limestone is composed solely of calcite.

Breccias are composed of basalt, basaltic glass, and limestone clasts in (1) calcite cement; (2) 

calcite-phillipsite cement, with fine-grained volcanogenic minerals; (3) calcite-smectite-phillipsite 

cement; (4) phillipsite cement, with fine-grained plagioclase and smectite. The limestone clasts 

consist of foraminiferal limestone and reef fossils such as coral, bryozoans, and benthic 

foraminifera.

YAP ARC SUBSTRATE ROCKS 

Descriptions and Composition

Substrate rocks based on dredges D5, D6, D8, and D9, in decreasing order of abundance are 

limestone, andesite and basalt, breccia, sandstone, serpentinite, and hydrothermal stratabound Mn 

deposits (Tables 5, 6). Carbonates consist of white to brown foraminiferal ooze; pale-brown, 

friable, burrowed, sandy foraminiferal limestone; pale-brown, argillaceous, burrowed micritic 

limestone with Mn veinlets interbedded with sandy foraminiferal limestone. Sand grains are 

basalt. A small amount of reef limestone and sandy chalk were also recovered. Foraminiferal 

sediment also comprise the matrix of some breccia samples. The limestones are composed of 

calcite and various amounts of volcanogenic minerals, chiefly plagioclase, and their alteration 

products, chiefly smectite (Table 7).

Volcanic rocks consist mainly of andesite, dacite, and basalt (Tables 6, 7, 10; KODOS, 

1999b). Basalts are brown, mottled greenish-pale brown, and gray-brown, altered, commonly 

plagioclase phyric, and show a brown, altered chill margin. Some samples are amygdaloidal, have 

calcite veins, or disseminated sulfides. Basalts consist chiefly of plagioclase and pyroxene, with 

minor amounts of magnetite, smectite, and hematite. Vesicles are lined with phillipsite or filled 

with smectite. A large hydrofracture vein in basalt sample D9-8D is composed of altered glassy 

basalt fragments in Mn oxide, smectite, and phillipsite cement with small grains of disseminated 

amphibole. Andesites are fresh to mildly altered (Table 10), gray, massive, vesicular, and 

plagioclase phyric; or black, plagioclase phyric, andesite glass with an altered, soft, gray rind. 

Andesite from dredge D5 is composed chiefly of plagioclase and pyroxene, with minor tridymite 

and quartz and the secondary minerals calcite and smectite. Andesite from dredge D7 is composed 

chiefly of tridymite, cristobalite, plagioclase, and pyroxene, with minor hematite and smectite. 

Phillipsite is abundant and magnetite occurs in moderate amounts in the alteration rind of andesite 

glass (Table 7, sample D9-6-2).
Breccia in dredge D5 is matrix supported and consists of clasts of volcaniclastic sandstone, 

andesite, breccia, and rarely hydrothermal(?) quartz in a fine-grained matrix of plagioclase, 

pyroxene, tridymite, smectite, and calcite (Table 6). Fe-Mn-oxide cement occurs near the contact 

with crusts. Two fragments of breccia consisting of serpentinite clasts in a quartz-calcite cement 

were also recovered. Breccia sample D5-2B is enriched in Au about 4 times over its earth's crust 

mean content of 4 ppb (Govett, 1983; Table 10). Breccia in dredge D8 is matrix supported and 

consist of altered brown basalt clasts in a pale-brown matrix of carbonate with blue serpentine 

grains, Mn oxides, and metamorphic rock fragments. Three types of breccia occur in dredge D9: 

1. Andesite and altered basalt clasts in clast-supported fine-grained volcaniclastic matrix; 2. Black 

andesite glass, andesite, and altered basalt in brown to yellow-green smectite matrix; 3. Gray, 

aphyric to feldspar phyric basalt and andesite clasts in yellow-green smectite matrix, phillipsite 

cement and veinlets, and Mn veinlets and grains.

Reworked pyroclastic rocks were recovered in dredge D9 and consist predominantly of 

sandstone, siltstone, and mudstone, which are commonly interbedded. Primary grains and glass 

have been completely replaced by phillipsite and smectite (Table 7). Different beds are black, 

brown, and yellow-green, display soft-sediment deformation and burrowing, and are peppered 

with Mn-oxide grains that also form laminae and graded beds. Smectite veins are also present. 

Gold is enriched about 4 times over its earth's crust mean content in some beds (Table 10). 

Volcaniclastic sandstone and siltstone consist of black glassy andesite grains with Fe-oxide and 

minor Mn-oxide cements (Fe2O3 is 19.5%, MnO is 0.88%, Table 10). The sandstone is composed 

of plagioclase, smectite, and X-ray amorphous Fe-oxide. Volcaniclastic siltstone and mudstone 

are pale-brown, yellow-green, and greenish, with Fe-Mn veinlets, dendrites, and grains. Those 

rocks are completely altered to smectite. The sandstone is enriched in Au about 6.5 times over its 

earth's crust mean content (Table 10).

Serpentinite from dredge D5 is partly replaced gabbro that is mottled white, dark-gray, bluegray, green, and yellow-brown, and is dense and heavy. The serpentinite is composed of 

serpentine (probably lizardite), pyroxene, plagioclase, and minor smectite, talc, tridymite, and 

magnetite as determined by XRD and also minor brucite, tremolite, chlorite, and hornblende as 

determined by thin-section petrography. The dominant replacement texture is bastite, indicating 

that pyroxene (less commonly amphibole) was the dominant mineral that was replaced (Wicks et 

al., 1977). Minor mesh texture also occurs, indicating replacement of minor olivine. Some 

replaced grains are laced with magnetite, which also forms veins, surrounds the margin of grains, 

and is disseminated. Serpentinite from dredge D8 is nearly completely replaced peridotite(?) that is 

brown with black patches and contains Mn dendrites, large lizardite plates, and extensive magnetite 

veins. Coarse-grained magnetite and lizardite indicate that the serpentinite is at a mature stage of 

development. The mineral composition is lizardite, magnetite, and chromite. The replacement 

texture is approximately 70% mesh and 30% bastite, indicating replacement predominantly of 

olivine and secondarily of pyroxene (Wicks and Whittaker, 1977; Wicks et al., 1977). Compared 

to other serpentinites (Faust and Fahey, 1962), serpentinites from dredges D5 and D8 have high Cr 

(to 3560 ppm) and Fe (to 10.3% Fe2O3) contents, reflecting their high contents of magnetite and 

chromite (Tables 7, 10).

LITAKPOOKI RIDGE FERROMANGANESE CRUSTS 

Description

Fe-Mn crusts collected during KODOS 98-3 vary in thickness from a patina to 154 mm (Tables 

5, 6). Dredge Dl had a maximum crust thickness of 120 mm and an average crust thickness of 80 

mm. Dredge D2 has a maximum crust thickness of 154 mm and an average crust thickness of 48 

mm. Thicker crusts are composed of two or more layers, five being the maximum and three and 

four layers being the most common. The typical bedding sequence is an uppermost massive black 

layer (layer 1); which is underlain by a black, porous to vuggy layer that is stained reddish (layer 

2); which in turn is underlain by a dense, massive, black, phosphatized layer (layer 3). Layer 3
may contain CFA-filled veins and lenses in addition to being impregnated by CFA. Layer 3 can be 

sub-divided into as many as four layers based on content and form of CFA and degree and 

orientation of fractures. All crusts greater than 60 mm thick have a phosphatized older crust 

generation. CFA in the 32-mm-thick crust D2-6A results from contamination from the substrate 

phosphorite, which has a gradational contact with the crust.

The growth rates and ages of nonphosphatized, or very mildly phosphatized bulk crusts and 

crust layers were determined using the empirical equation of Puteanus and Halbach (1988), which 

is based on Co contents and assumes a constant flux of Co in space and time, and that of Manheim 

and Lane-Bostwick (1988) (Table 11). The Puteanus and Halbach (1988) equation produces 

growth rates that range from 2.7 to 9.3 mm/Ma (mean 5.8 mm/Ma) for bulk crusts and 1.5 to 7.5 

mm/Ma (mean 4.0 mm/Ma) for crust layers. In contrast, growth rates determined by the Manheim 

and Lane-Bostwick (1988) equation are much slower, with a range for bulk crusts of 1.2 to 3.5 

mm/Ma (mean 2.4 mm/Ma) and for crust layers a range of 0.6-3.0 mm/Ma (mean 1.7 mm/Ma). 

The latter growth rates are much more in line with those determined by U-series and Be isotopes, 

which range from <1-10 mm/Ma, but mostly fall within the range of 1-3 mm/Ma (Hein et al., 

1999). Using the slower growth rates, the age range for the beginning of growth of bulk crusts is 

16.0-30.3 Ma. The 30.3 Ma age for the 100-mm-thick crust D1-1A is probably much too young 

and that age needs to be confirmed with Be isotope dating. The ages for initiation of crust growth 

are much younger than the age of the volcanic edifices on which they grew. Marshall Islands 

seamounts range in age from about 76-138 Ma old, ages of 76-86 Ma being most common (Davis 

et al., 1989; Lincoln et al., 1993). The fast growth rates determined by the Puteanus and Halbach 

(1988) equation produce unreasonably young ages for initiation of crust growth, especially for the 

thick crusts. Analytical precision in the chemical composition of the crusts produces growth rates 

and resulting crust ages with relative differences that range from 6-13%.

X-Ray Diffraction Mineralogy

Great care was taken in sampling crusts for chemical and mineralogical analyses. 

Contamination from recent sediments was removed, which was especially critical in porous crust 

layers. Also, special attention was paid to obtaining a clean separation of the lowest crust layer 

from the substrate; however, that was not possible with crust D2-6A where the contact was 

gradational. Any minerals or elements determined to exist in the various crust layers were 

incorporated into those layers during deposition or diagenesis and are not due to sampling 

procedures or post-depositional infiltration of sediment. Finally, encrusting organisms and other 

debris were cleaned from the crust surfaces before subsampling. Bulk always refers to the entire 

crust thickness, whether composed of layers or not.

6-MnO2 (vernadite) contents of bulk crusts and crust layers range from 69% to 100% (Table 

12). 6-MnO2 has only two X-ray reflections at about 2.42A and 1.41 A. X-ray amorphous Fe 

oxyhydroxide epitaxially intergrown with the 6-MnO2 is also a dominant phase in these crusts, but 

is not included with the crystalline phases listed in Table 12. Part of this X-ray amorphous iron 

phase crystallized to goethite in 56% of the layers analyzed. CFA occurs in 78% of the bulk crusts 

and 44% of the layers analyzed. Crust layer samples contain up to 26% CFA, always within the 

lowermost one or two layers of the crust. CFA is not found in the outer layers of thick crusts or in 

thin crusts. CFA is found in such a high percentage of the bulk crusts because most of the crusts 

analyzed are thick.

Quartz occurs in 24% of the samples analyzed; it was detected in 11% of the bulk crusts and 

31% of the crust layers (Table 12). Quartz contents are less than or equal to about 1%. 

Plagioclase (<1 to 7%) was found in six samples and K-feldspar in one sample. The quartz and 

some of the plagioclase are of eolian origin, earned by the westerlies from Asia, as there is no local 

or regional source for quartz in the west-central Pacific. The Marshall Islands are south of the 

main westerly wind belt which is reflected in lower quartz contents compared to crusts from higher 

latitudes (Hein et al., 1985, 1987; Hein, Kang, et al., 1990). The remainder of the plagioclase, as 

well as the smectite, phillipsite, K-feldspar, and calcite were reworked from local outcrops and
incorporated into the crusts during precipitation of the Fe-Mn oxyhydroxides. Smectite occurs in 

about 24% of the samples.

Calcite occurs in two crust layers. The outermost layer of crust D2-1B contains calcite that 

probably resides in the outermost few millimeters of that layer. Calcite is replaced by Fe-Mn 

oxyhydroxides after burial by more than a couple of millimeters of crust. Calcite in the inner layer 

(25-55 mm) of crust Dl-2 is probably the result of contamination.

Chemistry

Twenty-five Fe-Mn crust samples (9 bulk crusts and 16 crust layers) were analyzed for 

chemical composition (Tables 13-18). Data are presented including hygroscopic water (Table 13)

and on a hygroscopic water-free basis-that is normalized to 0% H2O" (Tables 14-17). 

Hygroscopic water varies from about 6% to 19% (to 30% in other samples from the region) and 

consequently can significantly affect the contents of all other elements. Sample compositions

normalized to 0% H2O can be more meaningfully compared and also more closely represent the 

grade of the potential ore. The following discussion is confined to hygroscopic water-free 

compositional data.

Bulk Crusts: The mean Fe and Mn contents of the 9 bulk crusts are 20.1% and 25.2%, 

respectively (Tables 14, 16). The mean Fe/Mn ratio (0.8) is higher than the mean ratio for the 

entire central Pacific region (0.72; Hein et al., 1992), the ratio for the entire Marshall Islands EEZ 

(0.64; Hein et al., 1999), and the ratio for the area to the northwest of the Marshall Islands EEZ 

(0.76; Hein et al., 1997a). For the entire Marshall Islands EEZ, the mean Mn content is more 

(26.3%), while the Fe content is less (16.9%) compared to bulk crusts from this study. The mean 

contents of the economically important metals Co (0.48%), Ni (0.34%), and Pt (0.54 ppm) are 

less than the mean contents of 0.79%, 0.57%, and 0.63 ppm, respectively, for the entire Marshall 

Islands EEZ (Hein et al., 1999). The mean Co and Ni contents are less and Pt about the same 

compared to mean contents for crusts from the entire equatorial Pacific region. Phosphorus, a 

potential byproduct of mining crusts for Co and Ni, has a mean value of 2.2%, higher than the 

central Pacific mean of about 1%, and the mean content of 1.8% for crusts from the entire Marshall 

Islands EEZ. Analysis of a large number of thick crusts lowers the mean contents of many metals, 

and that is probably why this study shows mean concentrations below the regional and Marshall 

Islands means for Co, Ni, and other metals. Studies that include only analyses of thin crusts yield 

mean concentrations higher than those of regional means (for example, Pichocki and Hoffert, 

1987; see Hein et al., 1992 for discussion). The Co+Ni+Cu mean content for all bulk crusts is 

0.92% and the maximum mean percent is 1.40%. If Pb is added to that group of elements, the 

mean content is 1.07% and the maximum mean content is 1.57%. The mean content of 

Co+Ni+Cu decreases with increasing crust thickness, for example the mean is 1.22%; for crusts 

<60 mm thick, and 0.83% for crusts >60 mm thick. That decrease in metals is controlled by Co 

and Ni contents because Cu contents increase in thick crusts, 0.07% for <6() mm-thick crusts 

versus 0.11% for crusts >60 mm thick. Mean Pb contents are about the same in thin and thick 

crusts. The relationship of Co+Ni+Cu to Fe and Mn contents can be seen on a Bonatti et al. 

(1972) diagram (Fig. 7), on which the KODOS 98-3 data fall in the range typical for central Pacific 

Fe-Mn crusts (Halbach et al., 1982; De Carlo et al., 1987; Hein et al., 1992).

Other metals of potential economic interest that are concentrated in the Fe-Mn crusts include Zr 

(535 ppm), Tl (121 ppm), Te (95 ppm), Bi (mean 52 ppm), W (-36 ppm), and Pt (0.5 ppm). 

Only recently have crusts been analyzed for Tl, Te, and Bi. Te contents are remarkably high 

compared to its earth's crust mean content of about 1 ppb-95,000 times enrichment for the Fe-Mn 

crust mean of 95 ppm and 145,000 times enrichment for the maximum Te content of 145 ppm in 

bulk crusts. However, the mean Te content of the earth's crust is poorly known and some 

estimates have placed it as high at 10 ppb, which would lower those enrichments by a factor of 10. 

The interesting aspect is that the mean content of two of those elements, Bi and Te increase in thick 

crusts, while Tl, Zr, and W decrease in thick crusts, that is, they are 39, 80, 159, 569, and 44 

ppm in <60 mm-thick crusts and 58, 102, 102, 519, and 32 ppm, respectively, in >6() mm-thick
crusts. Mean contents of Ca, P, S, As, Cr, Cu, Mo, Pb, Sr, Th, U, V, Y, and Pt increase in thick 

crusts, whereas the other elements decrease except for Be, Ga, Hf, Rb, Sb, Sc, Sn, Rh, and Os, 

which are about the same in both crust thickness groups. This means that the ore grade for some 

rare metals (Bi, Te, Pt) increases with tonnage (thickness), the reverse of the situation for Co in 

crusts, the chief metal of economic interest. This decrease in grade with increase in tonnage is 

typical for metals of interest in most types of ore deposits. The increases in Ca and P contents are 

the result of phosphatization of the older generation of thick crusts.

Crust Layers: Individual layers from five crusts were analyzed: Two crusts were split into 

four layers, two crusts into three layers, and one crust into two layers (Tables 14, 17). Crust D2-5 

was divided into two layers and the change in element contents is controlled by the high content of 

detritus in the inner layer. Therefore, Si, Al, and other aluminosilicate-associated elements are 

higher in the inner layer and Fe and Mn oxide-associated elements are higher in the outer layer 

(Table 14). For the crusts divided into three layers, Dl-1 shows uniform increases toward the 

substrate for Ca, P, Ba, Cu, (CFA associated elements) and Te and uniform decreases in Mn, B, 

Cd, Co, Ga, Ni, Tl, Hg, Ru, mostly Mn oxyhydroxide-associated elements. Aluminosilicateassociated elements are highest in the middle layer and residual biogenic-associated elements are 

lowest in the middle layer. For crust D2-2, there are uniform increases toward the substrate for 

Ca, P, Ba, Be, and Sr (CFA-associated elements), similar to Dl-1, and uniform decreases in Fe 

and Mn oxyhydroxide-associated elements. Aluminosilicate-associated elements are lowest in the 

middle layer and residual biogenic-associated elements are highest in the middle layer. For the 

crusts divided into four layers, Dl-2 shows uniform decreases to the substrate of Mn, B, Co, Tl, 

and Hg and a uniform increase in Cu. Only the lowermost layer of the crust is phosphatized. All 

other elements have maximum values in one of the four layers, with variable distributions in the 

other layers. For crust D2-1, there are uniform decreases to the substrate only for Cd and uniform 

increases for Be, Bi, and Sr. The lower two layers are phosphatized with layer 3 having the 

highest P content; consequently, most other elements have their highest contents in layer 1, 2, or 4. 

Platinum typically increases with depth in thick crusts, although here it increased in one crust and 

decreased in another. In general, the trends indicate that there is a decrease of manganophile 

elements with depth in the crusts accompanied by increases in elements characteristic of the 

residual biogenic phase. Non-phosphatized crust layers generally have higher trace metal contents 

relative to Fe and Mn contents than do phosphatized crust layers.

Platinum Group Elements and Gold

Four bulk crusts and six crust layers were analyzed for PGEs, and nine bulk crusts and 12 

crust layers for Au (Table 14). Mean palladium (mean 8 ppb), Os (2 ppb), and Au (~5 ppb) 

contents are roughly at their earth's crust mean content. One high Au outlier (54 ppb) raises the 

mean Au content to its earth's crust mean, otherwise it would be lower than its earth's crust mean. 

Two samples analyzed from the KODOS 97-4 cruise had high Au contents of 543 and 51 ppb, but 

overall crusts from that cruise had a mean Au content about at its earth's crust mean. The other 

PGEs are enriched over their earth's crust mean content by 7 times for Ir (Fe-Mn crust mean of 7 

ppb), 20 times for Ru (mean 20 ppb), 30 times for Rh (mean 31 ppb), and 130 times for Pt with a 

mean content of 648 ppb. Crust layer D2-2B has an uncommonly high Pt content of 1930 ppb, the 

maximum measured content being 2650 ppb (Hein et al., 1997a). The high content in D2-2B is 

especially unusual in that it occurs in the outermost layer of the crust rather than the innermost 

phosphatized layer, which is more common. That same layer has the highest Mn, Ti, Te, Sn, As, 

Sb, Nb, Au, Ir, Rh, and Ru contents measured in this study, all of which decrease toward the 

substrate; Co has its second highest content. These element enrichments are likely associated with 

the high Mn content, that is with the S-MnO2 phase. There is also an uncommonly low Pt content 

of 151 ppb for the outermost layer of crust D1-1B. The mean Pt content of 648 ppb is comparable 

to the mean for the entire RMIEEZ (634 ppb; Hein et al., 1999) and lower than the mean content 

for a large area of the northwest Pacific, 777 ppb (Usui and Someya, 1997).

Enrichment of PGEs in the inner parts of crusts is common for central Pacific crusts. The 

highest Pd and Ru concentrations occur in crusts from the Yap and Mariana arcs, as do other

10
elements indicative of clastic input. As shown in previous studies, Pt, Ir, and Rh are derived 

predominantly from seawater, whereas Pd and much of the Ru are derived from clastic debris, the 

remainder of the Ru being derived from seawater. The extraterrestrial component (meteorite 

debris) in the bulk crusts is small. However, meteorite debris may be concentrated locally in the 

crusts by formation of dissolution unconformities, or by proximity of the crust to meteorite fallout 

during formation of the layer. Localized extraterrestrial debris-rich horizons, however, do not alter 

the overall hydrogenetic signature of the PGEs. In addition, the PGE ratios are non-chondritic, 

with Fe-Mn crust compositions showing more than an order of magnitude more Pt relative to Ir 

and Rh relative to Ir. More likely, Pt is a redox sensitive element and its changing concentration 

reflects changing redox conditions, and diagenesis in the inner parts of the crusts (see Hein et al., 

1997b).

Rare Earth Elements

For 7 bulk crusts and 6 crust layers, total REEs vary from about 0.15% to 0.27% (Table 18). 

For bulk crusts, total REE contents range from 0.15% to 0.24%, with a mean of 0.20%. The 

range and mean for individual crust layers are somewhat higher than for bulk crusts, 0.15%;- 

0.27% and 0.21%, respectively. Mean total REE content differences between thick and thin crusts 

is 0.22% and 0.18%, respectively. The two samples for which layers were analyzed show 

different patterns of REE concentrations with depth in the crusts. The three layers of crust D1-1 

generally show a decrease of light REEs (La to Gd) from the innermost layer 3 to the outer two 

layers, which have similar contents; the heavy REEs (Gd-Lu) have their highest content in the 

outermost layer, next highest in the innermost layer and lowest content in the middle layer. Total 

REEs and the Ce anomalies follow the pattern of the light REEs. The three layers of crusts D2-2 

show the highest content of each element in the middle layer (except La), the next highest content 

in the lowermost layer, and lowest content in the uppermost layer. Total REEs follow the same 

pattern, but the Ce anomalies decrease from the surface to the substrate. These two trends are not 

related to degree of phosphatization of the crust layers. For crusts from the area northwest of the 

RMI, 11 of 13 crusts analyzed showed decreases in REE contents from the substrate to the crust 

surface (Hein et al., 1997a), as did total REEs for crust Dl-1 here.

Chondrite-normalized REE patterns show moderate to large positive Ce anomalies, small 

positive Gd anomalies, light REE enrichments, and slight decreases in heavy REEs with increasing 

atomic number, or flat heavy REE patterns (Figs. 8-10). PAAS shale-normalized REE patterns 

show nearly flat heavy REEs, light REE depletion, and positive Ce and Gd anomalies. A small 

positive Gd anomaly is typical of hydrogenetic Fe-Mn crusts and of seawater (Hein et al., 1988). 

In crust Dl-1, the Ce anomalies increase through the crust from the surface to the substrate, where 

as the opposite trend in seen in crust D2-2.

Element Associations

Correlation coefficients and Q-mode factor analysis coupled with X-ray diffraction mineralogy 

can be used to interpret which elements are associated with the mineral phases that make up Fe-Mn 

crusts. We analyzed correlation coefficient matrices and Q-mode factor analyses for three data sets 

including nine bulk crusts from Table 14 (Table 19; Fig. 11), four bulk crusts <62 mm (Table 20), 

and five bulk crusts >85 mm (Table 21; Fig. 12). We interpret the data for bulk crusts to indicate 

that the following elements are associated with the following phases. Detrital (aluminosilicate) 

phase: Si, Al, Fe, Ti, K, Na, Zr, B, Nb, Hf, Li, Y; Mn-oxyhydroxide phase: Mn, Tl, Co, Ni, 

Pb, Ga, Mo, Cd, Na, Bi; Fe-oxyhydroxide phase: Fe, As; CFA phase: Ca, P, S, Sr, As, 

Te, Bi, Ba, Be, Cu, Sn, Hf, Pb, Sc; residual-biogenic phase: Sr, Ba, Cu, W, Zn, As, V, Bi.

Only minor differences exist between the data sets of bulk crusts <62 mm thick and all bulk 

crusts, but significant differences exist for crusts >85 mm thick. It has been shown that element 

associations for very thick crusts do not follow those typical of Fe-Mn crusts because of extensive 

phosphatization and remobilization of elements (e.g. Hein, Kang, et al., 1990; Koschinsky et al., 

1997; Hein and Morgan, 1999). The detrital phase shows minor differences but the other three

11
phases are mixed (Table 21; Fig. 12): Mn-oxyhydroxide plus residual biogenic phase 

includes Mn, W, As, Sr, Bi, Cu, Zn, V, Ca, P, Ba, Pb, Ni; the CFA-diagenetic phase includes 

Te, Sn, P, Tl, Ca, Co, Nb, Pb, Ti, Bi. This latter phase contains those elements that are known to 

be, or thought to be, incorporated into Fe-Mn crusts through an oxidation reaction (Co, Pb, Te, Tl, 

Bi, Ti, Sn).

Element associations indicate that the rare metals (Te, Tl, W, Bi, Hf, Zr, Nb, Sn) are 

associated with several phases. Tl is clearly associated solely with the Mn-oxyhydroxide phase. 

Te may be associated primarily with the CFA phase, secondarily with the residual biogenic phase, 

and possible also with the Mn phase. Hf, Zr, and Nb are predominantly part of the detrital phase, 

but Hf may also, in part, be associated with the CFA phase, Zr with the residual biogenic phase, 

and Nb with each of the other three phases. Bi appears to be associated predominantly with the 

CFA phase and secondarily with the residual biogenic and Mn phases. W may be associated with 

the residual biogenic phase and secondarily with the Mn oxyhydroxide phase. Sn may be 

predominantly associated with the CFA phase and, in part, with each of the other three phases. Tl, 

Hf, and Zr associations are very consistent among the various data sets analyzed here, but the other 

rare metals need to be analyzed in greater detail with a larger data set.

Correlation coefficients also show that the following elements increase with increasing crust 

thickness: Ba, S, Bi, Ca, P, Be, and Sr, whereas Si, Cd, B, Al, and K decrease with increasing 

crust thickness. These relationships indicate that the CFA and residual biogenic phases increase 

and the detrital phase decreases with increasing crust thickness. It has been noted many times that 

Co contents, the most important metal of economic interest, decreases with increasing crust 

thickness, but that correlation is not seen here at the 95% confidence level.

YAP CONVERGENT MARGIN FERROMANGANESE CRUSTS AND 

STRATABOUND MANGANESE DEPOSITS

Description

Fe-Mn crusts collected on the YCM during KODOS 98-3 are thin and vary in thickness from a 

patina to 15 mm for Yap Arc samples (D5, D6, D8-, D9) and a patina to 10 mm for dredge D7 

from southwest Caroline Ridge (Tables 5,6). The Fe-Mn crusts are composed of one or two 

layers. Crust layers are black, massive, and porous and rarely dendritic or acicular. Crust 

surfaces are granular to smooth and rarely botryoidal. None of the crusts have been phosphatized.

Stratabound hydrothermal deposits consists of Mn oxyhydroxide-cemented volcaniclastic 

sandstone (D5) composed of medium sand-sized grains in gray to black cement; and a 15 mmthick, submetallic, gray layer of Mn oxyhydroxide with adjacent layers of Mn-cemented 

volcaniclastic sandstone (D8). The submetallic luster and gray color is a hallmark of hydrothermal 

Mn deposits.

Growth rates of the Fe-Mn crusts based on the Manheim and Lane-Bostwick (1988) equation 

(3.1-6.1 mm/Ma) are typical of hydrogenetic precipitation. Based on those growth rates, the oldest 

crust began forming only 2.6 Ma ago. The growth rate of the Stratabound hydrothermal Mn layer 

is about 38 mm/Ma, which is slow compared to other hydrothermal Mn deposits (e.g. Hein, Ahn, 

et al., 1992). That relatively slow growth rate is the result of an anomalously high Co content for 

hydrothermal Mn. The ages for initiation of crust growth are much younger than the age of the 

volcanic edifices on which they grew, which is Oligocene for southwest Caroline Ridge and 

Oligocene and Miocene for Yap Arc (Hein, Ahn, et al., 1992).

X-Ray Diffraction Mineralogy

8-MnO2 (vernadite) contents of bulk crusts range from 91% to 95% (Table 12). X-ray 

amorphous Fe oxyhydroxide epitaxially intergrown with the S-MnO2 is also a dominant phase in 

these crusts, but is not included with the crystalline phases listed in Table 12. Quartz, plagioclase,

12
and calcite occur as accessory minerals. Hydrothermal birnessite cements the volcaniclastic 

sandstone, which is composed of plagioclase, serpentine, pyroxene, amphibole, and quartz. The 

hydrothermal Mn layer is predominantly birnessite, with moderate smectite and quartz (Table 12). 

It is difficult to distinguish 8-MnO2 in the presence of birnessite because of overlapping peaks, so it 

is possible that 8-MnO2 occurs in addition to the birnessite.

Chemistry

Three bulk Fe-Mn crust samples, one Mn-cemented sandstone, and one stratabound Mn layer 

were analyzed for chemical composition (Tables 22-24).

Bulk Crusts: The mean Fe and Mn contents of the 3 bulk crusts are 22.2% and 22.6%, 

respectively (Tables 23, 24). The mean Fe/Mn ratio (1.0) is higher than the mean ratio for the 

entire central Pacific region (0.72; Hein et al, 1992), the Marshall Islands EEZ (0.64; Hein et al., 

1999), the area to the northwest of the Marshall Islands EEZ (0.76; Hein et al., 1997a), and Fe-Mn 

crusts from Litakpooki Ridge from this study; but is about the same as the ratio for the FSM EEZ, 

1.02 (Hein et al., 1999). Generally, island-arc Fe-Mn crusts form by both hydrogenetic and 

hydrothermal input and have Fe/Mn ratios greater than 1.0. However, only the bulk crust from 

southwest Caroline Ridge (D7) has more Fe than Mn. The Co contents, Fe/Mn ratios, and growth 

rates indicate that the YCM crusts are solely of hydrogenetic origin. The southwest Caroline Ridge 

crust is similar in composition to the Yap Arc crusts, but with somewhat higher Fe, Cl, Nb, Rb, 

and Zr contents and lower Al and Ba contents. The Caroline Ridge crust has an unusually high 

Si/Al ratio (>645) indicating a low detrital component and likely a high biogenic silica content.

Mean contents of the economically important metals Co (0.34%) and Ni (0.34%) are less than 

their mean contents (0.79% and 0.57%, respectively) for the RMI EEZ crusts (Hein et al., 1999). 

The Co+Ni+Cu mean content for bulk crusts is 0.75% and the maximum mean content is 0.86%. 

If Pb is added to that group of elements, the mean content is 0.86% and the maximum mean 

content is 0.98%. The relationship of Co+Ni+Cu to Fe and Mn (Fig. 7), show that the YCM 

samples have relatively less trace metals and more Fe compared to Litakpooki Ridge samples.

Other metals of potential economic interest that are concentrated in the YCM Fe-Mn crusts 

include Zr (554 ppm), Tl (98 ppm), Te (37 ppm), and Bi (mean 14 ppm). Zr is somewhat more, 

Tl somewhat less, and Bi and Te much lower that mean contents from Litakpooki Ridge crusts. 

The recovery of only thin crusts from the YCM limits their economic potential.

Stratabound deposits: The hydrothermal stratabound Mn-oxide layer (D8-1 A) has very 

high Mn (44%), Ba (1.18%), Ni (0.64%), and copper (0.2%) contents, as well as moderately high 

Zn (0.16%), Cd (16 ppm), and Li (179 ppm) contents, with an Fe/Mn ratio of 0.03 (Table 23). 

The high Mn and low Fe/Mn ratio are characteristic of hydrothermal Mn deposits. The high tracemetal contents are found in some hydrothermal Mn deposits (Hein et al., 1997b). Previously 

analyzed hydrothermal Mn samples (n=7) from Yap Arc also had high Mn (44%), Ni (0.45%), Ba 

(0.31%), Cu (0.26%), Zn (0.16%), Cd (44 ppm), and Cr (436 ppm) contents (Hein, Ahn, et al., 

1992), although the sample from this study has much higher Ni and Ba contents. Yap Arc 

hydrothermal Mn deposits have higher trace metal contents than similar deposits from other regions 

(Hein et al., 1997b), which may be the result of intensive leaching of ultramafic rocks by the 

hydrothermal fluids and the lack of precipitation of sulfides at depth, or the leaching of sulfides that 

formed at depth in the hydrothermal system. A high serpentinite content (Table 12) in the Mncemented sandstone (D5-16A) attests to the ubiquitous occurrences of ultramafic and mafic rocks 

in the Yap Arc, which had previously been dredged from outcrops and collected as blue-green 

muds that formed from serpentinite diapers (Hein, Ahn, et al., 1992).

Rare Earth Elements

Total REE contents for the 3 bulk crusts vary from 0.14% to 0.16%, with a mean of 0.15%; 

whereas the total REE contents for the hydrothermal deposits are very low, 130 ppm for the Mncemented sandstone and 34 ppm for the stratabound Mn layer (Table 18).

13
Chondrite-normalized REE patterns for the Fe-Mn crusts show small positive Ce and Gd 

anomalies, light REE enrichments, and decreases in heavy REEs with increasing atomic number 

(Fig. 13). These characteristics are typical of west Pacific hydrogenetic Fe-Mn crusts (Hein, Ahn, 

et al, 1992). PA AS shale-normalized REE patterns show nearly flat heavy REEs, light REE 

depletion, convex up middle REEs, and small positive Ce and Gd anomalies. The stratabound Mn 

layer shows a strong negative Ce anomaly, typical of hydrothermal Mn deposits, and a positive Eu 

anomaly, which reflects weathering of the basement rock and sediments by the mineralizing fluids 

(Fig. 14). The REE pattern for the Mn-cemented sandstone is very similar to those of the Fe-Mn 

crusts, but with an order of magnitude less enrichment relative to chondrites and shale. This 

indicates that there is a hydrogenetic component in the hydrothermal Mn-cemented sandstone. The 

negative Yb anomaly probably results from analytical error because of the very low contents of the 

heaviest REEs.

RESOURCE CONSIDERATIONS

The commonly cited cut-off grade for potential economic development is 0.8% Co and the cutoff thickness is 40 mm. On a water-free basis, KODOS 98-3 samples have moderate mean Pt 

(0.54 ppm), Mn (25.2%), Co (0.48%), Ni (0.34%), and Cu (0.10%) contents, with a mean 

Co+Ni+Cu content of 0.92%. The mean crust thickness is >40 mm for dredge hauls from 

Litakpooki Ridge, with one being 80 mm; none of the dredge hauls from the YCM yielded thick 

crusts. It is not known whether ultimately grade or tonnage (thickness) will be the most important 

factor in choosing a potential mine site, but if it is tonnage, then both Litakpooki Ridge and 

Lomilik Seamount in the RMIEEZ are excellent sites for additional work.

It is important that several very rare metals, such as the PGEs, Te, and Bi increase in grade 

with increasing crust thickness in the RMI crusts. Te contents are especially interesting because its 

earth's crust abundance may be as much as 5 times less than that of Pt, but its concentration in FeMn crusts is about 200 times greater than that of Pt. Te, Bi, Nb, Tl, W, and Zr need to be looked 

at in detail in terms of their resource potential in Fe-Mn crusts. Elevated gold contents in some of 

the dredged Yap Arc rocks indicate that epithermal gold deposits like those that occur on nearby 

Gagil-Tamil and Maap Islands may also occur offshore.

ACKNOWLEDGMENTS

We thank the captain, crew, and scientific staff of the R. V. Onnuri cruise KODOS 98-3 for 

excellent support while at sea. We thank Jane Reid, U.S. Geological Survey (USGS), for 

reviewing this report, and C. Degnan, D. Mosier, and F. Wong of the USGS for help with the 

maps.

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17
Table 1. Scientific personnel on R.V. Onnuri cruise KODOS 98-3

Jai Woon Moon

Kyeong Young Lee

James R. Hein

Malia Burrows

Youn-ji Choi

Jennifer S. Dowling

Raymond Freeman-Lynde

Young Geun Jin

Hoi Soo Jung

Hyun Sub Kim

Duk Kee Lee

Gun Chang Lee

Sang Heon Nam

Chan Young Park

Cheong Kee Park

Sung Hyun Park

Seung Kyu Son

In Sung Yoo_______

Co-chief scientist

Co-chief scientist

Geochemistry

Sampling CTD4

Sampling

Sedimentology

Airgun Seismic

Sampling

SBP, PDR

Airgun Seismic

Sampling DSC

Airgun Seismic

Data Processing

SeaBeam Bathymetry

Sampling

CTD

Airgun Seismic___

KORDI1

KORDI

USGS2

USGS

KORDI

USGS UGA3

KORDI

KORDI

KORDI

KORDI

KORDI

KORDI

KORDI

KORDI

KORDI

KORDI

KORDI

1 Korea Ocean Research and Development Institute 

2United States Geological Survey 

3University of Georgia, Athens

4 CTD = conductivity, temperature, density; SBP= sub-bottom profiler; PDR 

precision depth recorder; DSC = deep sea camera

18
Table 2. Station locations and operations for cruise KODOS 98-3

Station Operation1 Location

Marshall Islands Fe-Mn crust leg

SB 1 CTD1

SB 2 PCI

SB 3 PC2

SB 4 Dl

SB 5 D2

SB 6 D3

SB 7 D4

SB 8 CTD2

FSM Hvdrothermal leg

Litakpooki Ridge 

Litakpooki Ridge 

Litakpooki Ridge 

Litakpooki Ridge 

Litakpooki Ridge 

Litakpooki Ridge 

Litakpooki Ridge 

SW of Litakpooki

HI

H2

H3

H4

H5

H6

H7

H8

H9

H10

H 11

H 12

H13

H14

HIS

H 16

H17

H18

H19

H20

CTD3

CTD4

CTD5

BC1, 2

PC3

MCI

D5

D6

DSC1

CTD6

CTD7

CTD8

CTD9

MC2

D7

PC4

CTD 10

D8

D9

CTD11

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Trench

W. Caroline Ridge

W. Caroline Ridge

W. Caroline Ridge

W. Caroline Ridge

Yap Trench

Yap Arc

Yap Arc

Yap Arc

Yap Arc

CTD = conductivity, temperature, density, and oxygen profile; PC 

piston core; D = dredge; BC = box core; MC = multiple core; DSC = 

deep-sea camera

19
Table 3. Twelve channel, two-150 in3 airgun lines (AG); 3.5kHz and 12 kHz bathymetry 

lines (3.5, 12); and SeaBeam lines (SB) (see Figures 2, 3, and 5)

Location

Marshall Islands Fe-Mn crust

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Litakpooki Ridge

Lomilik Seamount

Lomilik Seamount

Lomilik Seamount

Lomilik Seamount

Lomilik Seamount

Lomilik Seamount

Lomilik Seamount

Lomilik Seamount

Lomilik Seamount

Lomilik Seamount

Lomilik Seamount

Subtotal

FSM Hydrothermal leg

Across Convergent Margin

Yap Arc

Across Convergent Margin

W. Caroline Ridge

Across Convergent Margin

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

Yap Arc

W. Caroline Ridge

W. Caroline Ridge

W. Caroline Ridge

W. Caroline Ridge

W. Caroline Ridge

W. Caroline Ridge

W. Caroline Ridge

W. Caroline Ridge

Subtotal

Total

Line Number

lep

SB1

SB 1-1

SB 2

SB 2-1

SB 3

SB 3-1

SB 4

SB 5

SB 6

SB 6-1

SB 7

SB 8

SB 9

SB 10

SB 11

SB 12

SB 13

SB 14

SB 15

SB 16

SB 17

SB 17-1

SB 17-2

SB 18

SB 19

SB 20

SB 21

SB 22

SB 23

-

HI

H 1-1

H2

H2-1

H3

H3-1

H4a

H4b

H4c

H4d

H4e

H5

H5-1

H6a

H6b

H6c

H6d

H6e

H6f

H6g

H7a

H7b

H7c

H7d

H7e

H7f

H7g

H7h

-

Operation

3.5, 12, SB

3.5, 12

3.5, 12, SB

3.5, 12

3.5, 12, SB

3.5, 12

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12

3.5, 12, SB

3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

AG, 3.5, 12, SB

-

Nautical Miles

23.78

4.98

23.79

4.98

23.79

2.49

16.85

7.47

23.80

4.98

23.80

25.79

28.21

23.29

30.41

3.67

7.07

9.35

26.41

4.35

11.73

3.24

11.40

2.8

26.32

14.41

17.38

26.23

6.65

439.42

78.9

5.1

78.9

8.2

78.8

3.0

10.2

5.6

4.8

8.6

7.6

20.3

5.6

17.8

2.5

2.1

2.0

2.2

4.9

12.7

4.9

7.3

2.2

3.0

3.0

3.8

4.1

10.0

397.8

837.2

Kilometers

44.04

9.22

44.05

9.22

44.06

4.61

31.21

13.83

44.07

9.22

44.08

47.76

52.25

43.14

56.31

6.8

13.09

17.31

48.91

8.06

21.72

6.00

21.11

5.18

48.74

26.68

32.19

48.57

12.31

813.74

146.1

9.4

146.1

15.2

146

5.6

18.8

10.3

8.9

16

14.1

37.6

10.3

33.0

4.6

3.9

3.7

4.0

9.0

23.5

9.0

13.5

4.0

5.6

5.5

7.0

7.5

18.5

736.7

1550.4

20
Table 4. Preliminary oxygen and temperature data from CTD casts, cruise KODOS 98-3 (see Figures 2 and 5)

Latitude

(N)

Longitude Station 

(E) Number

Julian 

Day

Greenwich Lowest O2 

Mean Content 

Time 1 (ml/1)

Water Depth 

at 

0

minimum 

2 (m)

Water Depth 

at Top of 

OMZ2 (m)

W

Is

Marshall Islands Fe-Mn crust lee

Litakpooki Ridge 

CTD2

CTD1

10°24.31'N

8°09.15'N

160°

161

°9.61'E

32.02'E

8

1

227

226

0827-1010

1327-1457

1.33

1.34

343

307

275

280

FSM Hydrothermal leg

Yap Arc

CTD 3

CTD 4

CTD 5

CTD 6

CTD 10

CTD 11

Yap Trench 

CTD 7 8°46.23'N

8°57.39'N

8°57.58'N

8°57.03'N

8°54.64'N

8°55.25'N

8°58.21'N

138°

137°

137°

137°

137°

137°

137°

08.15'E

34.94'E

41.05'E

40.96'E

37.73'E

32.04'E

28.67'E

19

28

25

18

11

10

9

236

238

237

236

235

234

234

0208-0651

0202-0418

0958-1200

2145-2335

1354-1600

1310-1510

0942-1216

2.04

1.94

2.06

2.07

2.03

1.98

2.01

434

419

482

479

467

440

406

310

275

360

300

340

350

350

W. Caroline Ridge

CTD 8

CTD 9 8°31.75'N

8°35.07'N

138°

138°

36.57'E

45.07'E

21

20

237

236

1423-1618

1200-1325

1.92

2.08

421

450

275

300

'Local Time equals GMT plus eleven hours for CTD 1 and 2 and GMT plus ten hours for CTD 3-11 

2OMZ = oxygen minimum zone
Table 5. Dredge summary for cruise KODOS 98-3 (see Figures 2 and 5)

to

to 

number 

Dredge 

Location

Marshall Islands Fe-Mn

D2A

Dl 

2

D2B2

D4

D3 

Litakpooki

Litakpooki 

Litakpooki

Litakpooki

Litakpooki 

Water depth 

on-off 

bottom (m)

crust leg

2700-2388

2200-1850 

1610-1468

1862-1680

2058-1893 

Water depth Recovery 

corrected (kg)

(m) 1

1600-1500

1840-1770

2040-1900 

: :

75

145

55 

Max. crust 

thickness 

(mm)

154

120 

1

Mean crust Dominant 

thickness substrate 

(mm)

80 Breccia 

4g3 Basalt, limestone

<1 Foram limestone

:: ::

Ironst

Comm

Large 

Mega

No re

No re

FSM Hydrothermal leg

D9

D8 

D7

D6 

D5 Yap Arc 

Yap Arc 

W. Caroline

Yap 

Ridge 

Arc 

Yap Arc 2676-2223

2672-1778 

2280-1778

2720-1779 

2757-2250 

2650-2450

2600-2350 

2250-1950

2720-1779 

2600-2350 

81

150 

122

1.3 

3.2 

15

6

10

11 3 Breccia 

<1 Pumice 

1 Basalt

< 1 Foram limestone 

3 Micritic limestone

Serpe

1 brec

Foram

Serpe

Andes

1 Depth interval from which samples were likely recovered

2Dredge repositioned because of ship's drift off station, clear change in rock types from lower to upper dredged samp

3Average for basalt substrate is 95 mm and for limestone substrate is 19 mm
Table 6. Location and description of dredge hauls, Marshall Islands Fe-Mn crust and FSM hydrothermal legs, KODOS 

to

Ui

Dredge

number

Dl

D2

Latitude

(ON) 1

08°13.97' 

08°13.42'

08°11.79'

08°10.77'

Longitude

(°E)

160°35.97' 

160°35.46'

160°34.48'

160°34.59'

Total

recovery

(kg)

55

220

Broken from

outcrop

(%)

100

99

Talus

(%)

0

1

Fe-Mn

encrusted

rock

100

66

Description of

ferromanganese oxides

Botryoidal surface, rarely granular to

smooth, granular on sides; Thick

crusts with 3 or 4 layers: 1. massive

black, 2. porous to vuggy, 3.

massive dense black, 4. where

present, an uppermost <10 mm 

massive layer; layer 3 may be 

subdivided into up to 4 layers by

bedding parallel fractures &

occurrence of CFA veins and blebs;

thinner crusts are missing layer 3; 2

nodules with large nuclei; some

breccia with Fe-Mn cement;

thickness: max=120 mm, av=80mm

Thick crusts on basal t+phosphorite:

Small/medium botryoids on surface,

granular on sides; 3 to 4 layers: 1.

black massive, 2. porous to vuggy &

columnar, Fe stained, 3. massive,

dense, black, disseminated CFA &

veins; layer 3 may be divided into an

upper layer without apparent CFA

and a lower layer with much CFA

&/or fractures; 4. Where present, an

uppermost <10mm massive layer; 

TTiin crusts on limestone &

phosphorite: Large to modified

botryoids on surface, granular on thin

crusts; 1-3 layers: 1. massive black,

2. porous, few vugs, 3. porous &

vuggy, impregnated limestone or

phosphorite; 1 completely encrusted

cobble with 3 layers: 1. acicular

black, 2. black, massive, fractured, 3.

massive, CFA veins and vug fill;

sparse granular crusts on friable

foram limestone; thickness on basalt:

max= 154mm, av=95mm; on

limestone: max=35mm, av=19mm;

on friable limestone: av=<lmm

70

pho

iro

CF

and 

Fe-

ph

(so

yel

peb

5% 

iro

rep

Ro

D2

enc

rep

sam

pla

oft

& 

lim

for

on 

ma

den

35

alte

am

Mn 

for

bro

wi
Table 6 continued

D3

D4

D5

D6

08°19.12'

08°19.01'

08°22.10'

08°23.06'

08°56.67'

08°54.38'

08°53.53'

08°51.81'

W43.421

160°42.55'

160°49.19'

160°44.45'

137°40.74'

137°4U7'

137°37.02'

137°41.36'

00

3.2

1.3

-

80

<1

-

20

>99

-

50

<1

No recovery

No Recovery

Smooth, granular, and

microbotryoidal surfaces; 1 or 2

layers: 1. black very porous, 2.

black, porous, dendritic; for one

layer=black, porous, massive; 1

sample of sandstone cemented by

hydrothermal Mn oxide; thickness:

max=llmm, av=3mm

Sparse, patchy, granular patina on

breccia fragment; none on pumice

No 

No 

60% 

san

in g

ma

oxi

Mn 

qua

wit

cal

mo

gre

hea

gre

sul

&/

vol

qua

vug

oxi

cha

sub

cor

98% 

bro

min

min

hyd
Table 6 continued

to

D7

D8

08°43.42'

08°42.69'

08°55.05'

08°53.71'

138°44.86'

138°45.24'

137°39.97'

137°42.54'

122

150

100

95

-52

75

<1

Granular to smooth surfaces; patchy

crust with 1 layer, black, porous, in

places capped by limestone;

foraminiferal limestone boulders with

sparse, patchy, granular crust; some

vesicles in basalt may be filled with

hydrothermal boxwork, Mn oxides;

thickness: max=10mm, av=lmm

Granular to smooth surfaces on

mostly patchy patina or thin crust; 1

layer, massive, black, porous, rarely

acicular; 1 piece of hydrothermal Mn

oxide, stratabound, submetallic gray

to black, massive to porous; crust

thickness: max=6mm, av=<lmm

68% 

ma

red

10-

alte

sm

to p

2. 

bro

am

enc

31% 

for

wit

1. b

and 

cem

tab

yel

+sm

3. g

sm

zeo

60% 

bro

fria

bro

bas

alte

oxi

ser

alte

bro

ser

me

sup

phy

Mn

ma
Table 6 continued

D9 08°50.18'

08°48.32'

137°35.07'

137°35.10'

81 90 10 60 Granular, smooth, & botryoidal

surfaces on mostly patchy

patina or thin crusts; 1 layer,

massive, black, porous, rarely

dendritic & acicular; 1 cobble of

andesite with 20 mm thick vein

of hydrofractured andesite clasts

in hydrothemial Mn oxide,

smectite, and phillipsite

cement; crust thickness:

max=15mm, av=<3mm

38% lim

brown, v

veinlets, 

with fora

grains; 2

gray, ma

phyric; 2

vesicular 

phillipsit

breccia, 

andesite 

altered v

silt & cla

glassy an

andesites

brown to 

some yel

gray to p

basalt & 

matrix o

veinlets, 

or tufface

mudstone

dark brow

sediment 

peppered 

form lam

mostly sm

sandston

black gla

gray mas

grained v

pebble

'Latitudes and longitudes for on and off bottom 

2Pumice
Table 7. X-ray diffraction mineralogy of substrate rocks from KODOS 98-3 cruise

Sample Majorl Moderate Minor/Trace Rock/Sediment

Marshall Islands Fe-Mn crust leg

D1-5A

D1-5B

D1-10A

D2-2E

D2-4B

CFA2, plagioclase

CFA, plagioclase

Calcite

Smectite

CFA

Smectite

CFA

-

-

Smectite

Halite

-

Phosphatized basalt clast from breccia3

Phosphatized hyaloclastite clast

Pebbly phosphatic limestone

Highly altered basalt

Phosphorite (Foraminiferal limestone)4

FSM Hydrothermal leg

D5-2B-C

D5-2B-M

D5-4A

D5-7A

D7-2-1A

D7-4-1A

D7-6-1A

D7-8-1A

D7-9-1A

D7-10-1A

D7-10-2A

D7-10-2B

D7-10-2C

D7-13A

D8-2A

D8-4A

D9-3-1A

D9-3-1B

D9-3-2A

D9-3-2B

D9-3-2C

D9-3-2D

D9-3-2E

D9-4A

D9-6-2A

D9-6-2B

D9-8C

D9-8D

D9-8E

D9-11-1A

D9-14A

Plagioclase, pyroxene

Plagioclase, pyroxene

Lizardite, pyroxene

Plagioclase

Plagioclase, pyroxene

Plagioclase, pyroxene

Plagioclase, pyroxene

Calcite

Calcite

Phillipsite, plagioclase

Calcite

Calcite

Phillipsite

Amorphous, plagioclase

Lizardite

Lizardite

Phillipsite

Smectite, phillipsite

Smectite, phillipsite

Smectite

Smectite, phillipsite

Phillipsite, smectite

Smectite, phillipsite

Tridymite, cristobalite

Cristobalite, plagioclase

Phillipsite, plagioclase

Smectite, phillipsite

Plagioclase

Phillipsite, plagioclase

Smectite, plagioclase

Calcite

Tridymite

Tridymite

Plagioclase

Pyroxene

-

Plagioclase, 

phillipsite

Smectite

-

Smectite

Calcite

Calcite

Magnetite

Magnetite

Magnetite

Phillipsite

-

-

Plagioclase, 

pyroxene

Pyroxene

Pyroxene, 

magnetite

Plagioclase

Pyroxene

-

-

Plagioclase

Smectite

Smectite, calcite

Smectite, magnetite, 

talc, tridymite

Tridymite, calcite, 

quartz, smectite

Magnetite, smectite, 

hematite

Magnetite, hematite, 

smectite

Magnetite, smectite, 

hematite

-

Smectite, hematite

Smectite

Phillipsite

Smectite

Smectite

Chromite

Chromite, smectite

Plagioclase, smectite

-

-

Hematite, smectite

Smectite

-

Hematite, smectite

Amphibole

-

High-Mg calcite, 

smectite

Volcaniclastic sandstone clast from breccia

Altered clay matrix of D5-2B-C

Serpentinite

Amygdaloidal andesite

Pillow basalt with chill margins

Altered pillow basalt

Vesicular pillow basalt fragment

Breccia matrix

Breccia matrix

Dark green matrix in breccia

White matrix in breccia

Green matrix in breccia

Brown-rind on clast from breccia

Volcanic ash bed in limestone

Serpentinite

Serpentinite

Sandy layer in bedded tuff

Mudstone layer in bedded tuff

Pale brown mudstone layer in bedded tuff

Green-gray sandstone layer in bedded tuff

Pale brown mudstone layer in bedded tuff

Brown sandstone layer in bedded tuff

Mottled brown siltstone layer in bedded tuff

Andesite

Black glassy andesite

Gray rind on glassy andesite

Yellow and white vein in basalt

Basalt

Vein in basalt

Volcaniclastic sandstone

Limestone and micritic limestone

iMajor: >25%, Moderate: 5-25%, Minor: <5%; 2CFA 

and most are Volcaniclastic; 4Rock type in parentheses

is carbonate fluorapatite; 3AH breccias are sedimentary, 

is replaced by CFA

27
Table 8. Chemical composition of substrate rocks from Litakpooki Ridge, 

Marshall Islands Fe-Mn crust leg, KODOS 98-3 cruise

SiO2 wt%

A12O3

FeO

Fe2O3

MgO

CaO

Na2O

K2O

TiO2

P205

MnO LOI2

Total

H20+

H2OCO2

t-total

^total

F

Cl

Ba ppm

Cr

Nb

Rb

Sr

Y

Zr

Th

U

CaO/P2O5

Rock type

D1-10A

0.78

0.24

~

0.22

0.34

54.2

0.21

0.05

0.024

10.0

0.09

33.0

99.2

0.6

0.20

32.4

9.00

0.20

0.918

0.051

44

<68

<2

<2

650

16

8

0.4

1.7

5.42

Phosphatic

limestone

D1-10A1

0.78

0.24

--

0.22

0.34

54.1

0.22

0.05

0.024

10.0

0.09

33.1

99.2

0.6

0.20

32.3

9.01

0.19

0.931

0.050

45

<68

2

<2

653

17

7

0.4

1.6

5.41

Phosphatic

limestone

D2-2E

43.0

18.0

<0.1

12.4

1.91

6.42

2.28

1.61

2.490

2.98

0.03

7.10

98.3

6.6

4.50

0.44

~

--

--

~

78

340

14

30

248

147

186

--

~

2.15

Altered

basalt

D2-2E1

42.8

18.0

<0.1

12.5

1.90

6.41

2.27

1.62

2.498

2.99

0.03

7.05

98.2

6.4

4.40

0.42

-

-

~

77

340

13

29

249

147

185

~

2.14

Altered

basalt

D2-4B

4.45

1.87

<0.1

1.73

0.62

48.7

1.27

0.13

0.169

29.8

0.50

7.80

97.1

2.4

0.60

4.92

-

-

--

~

162

<68

5

3

1260

254

91

~

1.63

Phosphorite

Duplicate analysis

= loss on ignition at 925° C; dash means not analyzed

28
Table 9. Yttrium and rare earth element 

contents (in ppm) of a partly phosphatized 

limestone, Marshall Islands Fe-Mn crust leg, 

KODOS 98-3 cruise

Y

La

Ce

Pr

Nd

Sm

Eu

Gd

Tb

Dy

Ho

Er

Tm

Yb

Lu

XREEs

Ce*

Y/Ho

D1-10A

16

8.7

5.7

1.3

5.8

1.4

0.38

1.7

0.2

1.5

0.37

1.2

0.2

1.3

0.22

30.0

0.4

43

D1-10A1

17

8.9

6.0

1.3

5.7

1.4

0.38

1.6

0.2

1.5

0.35

1.1

0.2

1.3

0.22

30.2

0.4

49

Duplicate analysis;

Ce* is Ce anomaly = chondrite-normalized 

2Ce/La+Pr

29
Table 10. Chemical composition of substrate rocks from FSM hydrothermal leg, KODOS 98-3 cruise

LO

SiO2 Wt%

A12O3

FeO

Fe203

MgO

CaO

Na2O

K2O

TiO2

P2Os

MnO

LOI2

Total

H20+

H2cr

C02

As ppm

Ba

Cr

Nb

Rb

Sb

Sr

W

Y

Zr

Au ppb

Rock type

D5-2B

49.8

14.0

2.0

5.96

10.4

9.79

1.70

0.52

0.372

0.03

0.11

2.25

96.93

1.8

3.10

0.02

<2

<20

550

6

<2

<0.5

37

<2

11

30

16

Breccia

D5-4A

42.9

8.52

3.5

5.11

22.4

6.63

0.69

0.19

0.200

0.04

0.13

6.35

96.66

6.3

0.90

0.03

<2

<20

2390

5

4

<0.5

29

<2

2

24

<5

Serpentinite

D7-2-1A

46.4

13.1

6.4

8.49

4.73

9.32

2.97

0.52

3.179

0.53

0.25

0.80

96.69

1.5

1.10

0.07

_

22

68

15

5

167

66

192

--

Basalt

D7-4-1A

46.2

18.8

2.5

10.5

1.51

11.1

3.91

0.46

1.511

0.23

0.19

1.70

98.63

1.7

0.30

0.46

_

41

270

8

6

298

24

75

~

Basalt

D7-6-1A

45.4

13.6

6.3

8.60

4.53

9.81

3.07

0.41

3.319

0.62

0.26

0.55

96.47

1.3

0.08

0.07

__

70

68

19

12

184

71

191

~

Basalt

D7-9-1A

38.3

11.3

11.7

3.13

14.7

2.18

2.34

2.081

0.14

0.21

12.9

98.98

3.2

<0.01

8.70

_

48

68

10

45

228

26

123

--

Breccia

D8-2A

39.5

0.67

1.4

10.3

34.4

0.33

0.23

0.04

0.018

0.06

0.08

12.3

99.37

11.3

1.30

0.04

23

<20

3560

6

<2

1.4

12

<2

<2

14

<5

Serpentinite

D9-3-1A

46.8

13.7

<0.1

16.3

3.45

1.91

2.16

3.79

1.065

0.08

0.52

8.00

97.88

7.6

5.70

0.04

7

112

68

12

64

4.0

104

4

9

208

15

Tuffaceous

sandstone

D9-3-1B

48.2

16.4

<0.1

13.2

3.81

2.16

2.22

2.62

0.820

0.11

0.95

8.50

99.09

6.8

6.10

0.07

9

170

140

11

37

3.2

138

<2

15

98

<5

Tuffaceous

mudstone

D

A

Duplicate analysis

2LOI = loss on ignition at 925° C; -- = not analyzed
Table 11. Calculated growth rates and ages of bulk Fe-Mn crusts and crust layers that have 

<2% P content, KODOS 98-3 cruise

Sample Interval 

(mm)1

Type Growth rate 

(mm/Ma)2

Crust age

(Ma)

Growth rate 

(mm/Ma)3

Crust age

(Ma)

Marshall Islands Fe-Mn crust cruise

D1-1A

D1-1A4

D1-1B

D1-1C

D1-2B

D1-2C

D1-2D

D1-4A

D2-1B

D2-1C

D2-1C4

D2-2B

D2-4A

D2-5A

D2-6A

0-100

0-100

0-7

7-37

0-10

10-25

25-55

0-45

0-10

10-60

10-60

0-30

0-25

0-20

0-32

Bulk

Bulk

Layer

Layer

Layer

Layer

Layer

Bulk

Layer

Layer

Layer

Layer

Bulk

Layer

Bulk

9.3 

8.4 

2.8 

6.7 

4.2 

6.6 

7.5 

4.2 

1.5 

3.0 

3.3 

1.8 

2.7 

2.6 

4.5

10.8

11.9

2.5

7

2.4

4.7

8.7

10.7

6.7

23.4

21.9

16.7

9.3

7.7

7.1

3.5 

3.3 

1.2 

2.8 

1.9 

2.8 

3.0 

1.9 

0.6 

1.3 

1.5 

0.7 

1.2 

1.1 

2.0

28.6

30.3

5.8

16.5

5.3

10.7

20.7

23.7

16.7

55.2

50.0

42.8

20.8

18.2

16.0

FSM Hvdrothermal cruise

D5-2A

D5-2A4

D7-11A

D9-5-1A

D9-6-1A

D8-1A

0-8 Bulk

0-8 Bulk

0-5 Bulk

0-5 Bulk

0-9 Bulk

Stratabound Mn

8.0

8.5

15.4

12.0

44.1

~

1.0

0.9

0.3

0.4

0.2

3.1

3.3

4.5

4.0

6.1

38.3

2.6

2.4

1.1

1.3

1.5

0.4

'Intervals measured from the outer surface of crusts

2From equation of Puteanus and Halbach (1988); age of a layer is for the base of that layer

3From equation of Manheim and Lane-Bostwick (1988)

4Duplicate sample

31
Table 12. X-ray diffraction mineralogy of Fe-Mn crusts and hydrothermal deposits from Marshall 

Islands and FSM, KODOS 98-3 cruise

Sample Type & Interval 

(mm) 1

5-MnO2

(%)2

Others

(%)

Marshall Islands Fe-Mn crust leg

D1-1A

D1-1B

D1-1C

D1-1D

D1-2A

D1-2B

D1-2C

D1-2D

D1-2E

D1-3A

D1-4A

D2-1A

D2-1B

D2-1C

D2-1D

D2-1E

D2-2A

D2-2B

D2-2C

D2-2D

D2-3A

D2-4A

D2-5A

D2-5B

D2-6A

Bulk (0-100)

Layer (0-7)

Layer (7-37)

Layer (37-102)

Bulk (0-95)

Layer (0-10)

Layer (10-25)

Layer (25-55)

Layer (55-90)

Bulk (0-62)

Bulk (0-45)

Bulk (0-142)

Layer (0-10)

Layer(10-60)

Layer (60-100)

Layer (100-150)

Bulk (0-98)

Layer (0-30)

Layer (30-47)

Layer (47-82)

Bulk (0-1 10)

Bulk (0-25)

Layer (0-20)

Layer (20-35)

Bulk (0-32)

95

98

99

87

91

96

94

95

85

94

97

95

99

99

82

93

90

100

88

74

92

99

94

69

93

4-CFA, 1-goethite

2-smectite

1-goethite

13-CFA,<1 -quartz

6-CFA, 2-pyroxene , 1- smectite

4-smectite

2-plagioclase, 2-pyroxene, 1 -quartz, 1-goethite

2-goethite, 1-plagioclase, 1 -quartz , <1- calcite

12-CFA, 2-smectite, 1-goethite

6-CFA

3-K-feldspar

5-CFA

1 -calcite

1-goethite

1 6-CFA, 2-goethite

5 -CF A, 1 -goethite, < 1 -quartz

10-CFA

~

8-CFA. 3-phillipsite, 1-goethite

26-CFA

6-CFA, 2-smectite

1-plagioclase

4-smectite, 1-plagioclase, 1 -quartz

14-CFA, 9-phillipsite, 7-plagioclase, 1-goethite

5-CFA, 1-plagioclase, 1 -quartz

FSM Hydrothermal leg

D5-2A

D5-16A

D7-11A

D8-1A

D9-5-1A

D9-6-1A

Bulk (0-8)

Mn sandstone

Bulk (0-5)

Stratabound Mn

Bulk (0-5)

Bulk (0-9)

94

?

94

9

95

91

5-plagioclase, 1 -calcite

25-birnessite, 50-plagioclase, 1 2-serpentine, 

6-pyroxene, 4-amphibole, 3-quartz

2-calcite, 2-plagioclase, 2-quartz

78-birnessite, 17-smectite, 5-quartz

3-plagioclase, 1 -calcite, 1 -quartz

5-quartz, 2-calcite, 2-plagioclase

1 Intervals measured from the outer surface of crusts;

2Percentages were determined by using the following weighting factors relative to quartz set at 1: 8-MnO2 70; 

todorokite 10; birnessite 12 (Hein et al., 1988); carbonate fluorapatite (CFA) 3.1; plagioclase 2.8; calcite 1.65; 

smectite 3.0; goethite 7.0; phillipsite 17.0; illite 6.0; pyroxene 5.0; halite 2.0 (Cook et al., 1975); the limit of 

detection for each mineral falls between 0.2 and 1.0%, except the manganese minerals which are greater, perhaps 

as much as 10% for 8-MnO2

32
Table 13. Chemical composition of Fe-Mn oxyhydroxide crusts from Marshall Islands Fe-Mn crust leg, KODOS 98-3 cruise

Fe wt%

Nfa

Fe/Mn

Si

Na

Al

K

Mg

Ca

Ti

P

S

H2 0'

LOI

As ppm

B

Ba

Be

Bi

Cd

a

Co

Cr

Cu

Ga

Hf

Li

Ma

Mb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

Tl

U

V

w

Zn

Zr

Au ppb

Hg

Ir

Os

Pd

Pt

Rh

Ru

Interval

Type

DMA

18.5

23.7

0.8

2.71

1.08

0.34

0.36

0.89

5.79

1.305

1.50

0.21

16.6

18.7

198

178

3140

9.9

47.0

0.7

6560

3150

189

1150

61

8

3

497

37

2510

1310

15

34.9

6.6

6

1440

65.3

10.2

73.3

<0.5

646

<4

576

499

<2

<5

4

2

4

470

22

20

0-100

Bulk

DMA 1

18.5

23.5

0.8

2.70

1.08

0.34

0.36

0.89

5.76

1.297

1.51

0.21

16.3

18.6

170

184

3150

10.7

45.0

1.2

6440

3290

171

1180

63

7

3

515

36

2700

1360

16

27.8

6.7

8

1480

69.8

10.0

73.4

<0.5

727

<4

612

502

<2

<5

..

-

-

0-100

Bulk

D1-1B

18.9

26.5

0.7

3.17

1.30

0.21

0.42

1.04

2.66

1.273

0.48

0.24

13.9

20.1

-

228

1970

7.5

42.0

0.7

7230

6000

-

370

28

2

492

40

2990

1460

11

-

5.6

7

1400

56.4

152

-

648

528

513

5

9

2

2

6

130

12

20

0-7

Layer

D1-1C

20.7

21.7

1.0

4.77

1.25

0.89

0.52

0.97

2.90

1.659

0.58

0.17

17.6

17.9

200

204

2610

9.6

37.8

0.2

7850

3560

182

872

24

15

2

344

57

2300

1090

7

31.1

5.5

11

1300

64.3

6.5

91.0

11.5

556

74

635

652

<2

7

4

-

4

320

21

18

7-37

Layer

D1-1D

15.7

18.4

0.9

2.20

0.84

0.33

0.20

0.74

12.9

1.064

4.19

0.27

15.0

16.5

185

147

2800

9.4

58.5

<0.2

5330

2230

183

1280

23

8

<1

423

31

1940

1300

9

32.1

5.4

9

1500

74.0

14.5

59.4

8.0

610

<4

549

367

6

<5

4

-

8

410

19

10

37-102

Layer

D1-2A

18.1

19.7

0.9

4.03

1.07

0.83

0.42

0.89

7.72

1.302

2.25

0.24

6.90

16.2

170

197

2860

11.1

45.8

0.8

6840

3320

<2

955

48

13

2

362

43

2840

1130

12

26.3

7.0

9

1500

71.8

<0.5

94.7

<0.5

676

<4

719

524

<2

6

--

-

-

-

0-95

Bulk

D1-2B

20.7

24.4

0.8

4.03

1.31

0.50

0.47

1.02

2.59

1.608

0.45

0.18

10.5

17.9

-

242

2200

9.3

34.6

1.7

6950

4890

-

481

74

-

2

424

45

3190

1380

14

-

5.5

8

1340

56.6

-

122

-

704

-

626

481

-

16

-

-

-

-

-

0-10

Layer

D1-2C

19.4

20.9

0.9

5.84

1.39

1.34

0.67

1.00

3.41

1.603

0.71

0.17

11.3

16.3

165

202

3430

10.1

39.7

2.1

7430

3850

41

866

79

12

5

307

55

3250

1070

17

25.2

5.4

12

1260

80.1

<0.5

112

<0.5

624

<4

708

585

<2

9

..

-

--

10-25

Layer

D1-2D

21.0

21.3

1.0

4.96

1.21

1.01

0.58

1.00

3.22

1.598

0.62

0.15

9.40

17.0

-

206

2560

11.4

33.6

1.5

8250

3730

-

894

46

-

3

342

64

3200

1100

12

-

5.4

15

1260

76.6

-

104

705

-

741

685

-

8

-

..

-

-

-

25-55

Layer

D1-2E

15.3

15.3

1.0

3.51

1.02

0.93

0.31

0.81

13.7

0.862

4.67

0.28

6.30

14.7

135

155

2170

10.0

44.2

0.5

5290

1780

28

1170

40

13

5

281

27

2880

935

16

23.2

8.8

11

1440

57.4

6.3

60.4

13.2

552

<4

679

442

<2

6

--

..

-

-

-

55-90

Layer

D1-3A

18.0

18.4

1.0

3.96

1.02

0.85

0.41

0.84

9.01

1.268

2.76

0.26

8.60

16.3

206

188

2500

10.1

50.1

0.4

6650

3290

174

1210

26

12

2

398

45

2220

1170

13

31.7

8.3

8

1480

91.5

11.8

69.1

11.6

607

<4

627

488

<2

9

-

-

-

-

0-62

Bulk
Table 13 continued

Fe wt%

Mn

Fe/Mn

Si

Na

Al

K

Mg

Ca

Ti

P

S

H2Cf

LOI

As ppm

B

Ba

Be

Bi

Cd

a

Co

Cr

Cu

Ga

Hf

Li

Mo

Nb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

Tl

U

V

w

Zn

Zr

Au ppb

Hg

Ir

On

Pd

Pt

Rh

Ru

Interval

Type

D2-1C

19.3

25.6

0.8

3.40

1.22

0.62

0.46

1.05

2.87

1.560

0.48

0.22

12.2

18.7

169

188

2270

9.0

41.7

1.9

9770

5850

<2

917

58

11

2

449

58

4260

1210

19

23.1

5.7

12

1260

101

<0.5

176

<0.5

615

<4

692

566

<2

<5

--

-

..

-

-

10-60

Layer

D2-1C1

19.2

25.4

0.8

3.40

1.22

0.63

0.46

1.04

2.85

1.553

0.47

0.19

12.3

18.8

157

200

2280

10.1

45.6

1.7

9550

5470

<2

940

47

10

2

426

59

4350

1100

20

22.6

5.4

13

1270

104

6.2

164

<0.5

659

<4

653

567

<2

<5

--

-

-

-

-

-

10-60

Layer

D2-1D

14.5

17.1

0.8

1.94

0.82

0.35

0.17

0.72

14.7

0.847

4.93

0.31

6.30

16.0

171

153

2140

10.3

68.8

<0.2

6120

2420

<2

914

51

9

3

391

25

2430

1060

12

21.5

10.2

9

1460

72.7

14.7

87.9

<0.5

644

<4

557

375

<2

6

--

-

-

-

-

-

60-100

Layer

D2-1E

18.4

22.1

0.8

2.86

0.96

0.43

0.39

0.80

6.97

1.659

1.88

0.27

9.40

17.1

160

166

4180

15.2

81.0

<0.2

9090

3250

<2

730

55

11

2

553

55

2490

2170

19

32.7

5.7

9

1550

127

13.5

101

10.6

814

<4

633

510

<2

<5

--

-

-

-

100-150

Layer

D2-2A

15.0

21.4

0.7

1.80

0.91

0.23

0.21

0.80

11.3

1.325

3.49

0.26

14.1

17.5

181

138

2730

8.4

54.6

<0.2

6670

4200

163

700

25

8

<1

419

42

2300

1440

17

31.0

5.0

10

1430

109

16.0

112

15.4

563

<4

511

359

<2

<5

6

2

6

620

29

14

0-98

Bulk

D2-2B

18.0

28.2

0.6

2.20

1.25

0.15

0.35

1.04

2.94

1.713

0.38

0.19

17.1

20.4

210

158

2430

7.0

53.0

1.4

9680

8030

158

993

31

11

<1

401

86

3720

1450

15

35.8

5.5

16

1280

158

14.4

172

<0.5

541

<4

621

543

45

5

14

2

10

1600

70

34

0-30

Layer

D2-2C

14.5

24.6

0.6

1.37

0.91

0.06

0.22

0.85

9.86

1.253

2.84

0.32

10.0

18.8

-

143

2810

8.5

88.0

<0.2

7120

5430

-

947

34

-

<1

591

38

2990

1820

10

-

6.6

9

1630

143

-

154

-

611

-

629

394

-

6

6

2

4

700

27

12

30-47

Layer

D2-2D

14.6

16.1

0.9

1.88

0.79

0.44

0.16

0.66

15.1

1.445

5.19

0.32

7.30

14.9

184

136

3130

10.6

80.4

0.7

5710

2710

140

535

27

8

1

370

43

1400

1880

14

37.0

4.2

8

1750

125

9.8

82.8

<0.5

545

<4

536

310

<2

<5

4

..

4

540

24

8

47-82

Layer

D2-3A

16.2

23.0

0.7

2.09

0.93

0.28

0.29

0.86

9.36

1.104

2.77

0.28

15.7

17.7

197

146

2920

8.1

53.7

0.5

6520

3600

145

914

29

8

3

581

30

2650

1350

15

28.5

6.0

6

1510

71.1

11.4

61.4

12.7

617

144

628

353

<2

<5

4

6

340

16

12

0-110

Bulk

D2-4A

18.0

26.3

0.7

3.89

1.27

0.65

0.47

1.09

3.07

1.496

0.46

0.20

8.80

18.5

172

211

1940

7.5

43.2

2.5

7350

6440

<2

434

51

5

3

486

42

5010

1430

15

23.1

4.6

8

1210

73.4

<0.5

182

<0.5

631

<4

651

445

<2

8

--

-

-

-

-

0-25

Bulk

D2-5A

18.2

26.5

0.7

3.60

1.29

0.59

0.50

1.08

2.64

1.437

0.41

0.20

9.70

18.5

169

213

2000

7.8

40.4

2.0

7540

6640

<2

381

64

<1

2

486

45

4690

1500

16

25.7

4.4

8

1220

68.6

5.0

165

<0.5

646

<4

651

462

<2

8

-

-

0-20

Layer

All Ag contents <0.2ppm; Br <lppm 

^Duplicate analysis of sample

Cs <3ppm; Ge <10ppm; In <0.5ppm; Se <5ppm; Ta <lppm
Table 14. Hygroscopic water-free (0% H2O") composition of Fe-Mn crusts from Table 13

Fe wt%

Mn

Fe/Mn

Si

Na

Al

K

Mg

Ca

Ti

P

S

As ppm

B

Ba

Be

Bi

Cd

a

Co

Cr

Cu

Ga

Iff

Li

Kb

Nb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

Tl

U

V

W

Zn

Zr

Au ppb

Hg

Ir

a

Pd

Pt

Rh

Ru

Interval

Type

DMA

22.1

28.4

0.8

3.25

1.29

0.41

0.43

1.07

6.94

1.564

1.80

0.25

237

213

3765

11.9

56.4

0.8

7866

3777

227

1379

73

10

4

596

44

3010

1571

18

41.8

7.9

7

1727

78.3

12.2

87.9

<0.6

775

<5

691

598

<2

<6

5

2

5

564

26

24

0-100

Bulk

DMA'

22.1

28.1

0.9

3.23

1.29

0.40

0.43

1.07

6.88

1.549

1.80

0.25

203

220

3763

12.8

53.8

1.4

7694

3931

204

1410

75

8

4

615

43

3226

1625

19

33.2

8.0

10

1768

83.4

11.9

87.7

<0.6

869

<5

731

600

<2

<6

-

-

-

-

-

0-100

Bulk

DMB

21.9

30.8

0.7

3.69

1.51

0.25

0.49

1.21

3.09

1.479

0.55

0.28

--

265

2288

8.7

48.8

0.8

8397

6969

-

430

33

-

2

571

46

3473

1696

13

-

6.5

8

1626

65.5

-

177

-

753

..

613

596

6

10

2

2

7

151

14

23

0-7

Layer

D1-1C

25.1

26.3

1.0

5.79

1.51

1.09

0.63

1.18

3.52

2.014

0.70

0.21

243

248

3167

11.7

45.9

0.2

9527

4320

221

1058

29

18

2

417

69

2791

1323

8

37.7

6.7

13

1578

78.0

7.9

110

14.0

675

90

771

791

<2

8

5

-

5

388

25

22

7-37

Layer

DMD

18.4

21.6

0.9

2.59

0.99

0.39

0.23

0.87

15.1

1.252

4.93

0.32

218

173

3294

11.1

68.8

<0.2

6271

2624

215

1506

27

9

<1

498

36

2282

1529

11

37.8

6.4

11

1765

87.1

17.1

69.9

9.4

718

<5

646

432

7

<6

5

9

482

22

12

37-102

Layer

D1-2A

19.5

21.2

0.9

4.33

1.15

0.89

0.45

0.95

8.29

1.398

2.42

0.26

183

212

3072

11.9

49.2

0.9

7347

3566

<2

1026

52

14

2

389

46

3050

1214

13

28.2

7.5

10

1611

77.1

<0.5

102

<0.5

726

<4

772

563

<2

6

..

--

-

0-95

Bulk

D1-2B

23.1

27.3

0.8

4.50

1.46

0.56

0.53

1.14

2.90

1.797

0.51

0.20

-

270

2458

10.4

38.7

1.9

7765

5464

-

537

83

-

2

474

50

3564

1542

16

6.1

9

1497

63.2

-

136

-

787

..

699

537

-

18

--

..

-

-

0-10

Layer

D1-2C

21.8

23.6

0.9

6.59

1.56

1.51

0.76

1.12

3.84

1.807

0.80

0.19

186

228

3867

11.4

44.8

2.4

8377

4340

46

976

89

14

6

346

62

3664

1206

19

28.4

6.1

14

1421

90.3

<0.6

126

<0.6

703

<5

798

660

<2

10

-

-

-

-

10-25

Layer

D1-2D

23.2

23.5

1.0

5.47

1.33

1.11

0.64

1.11

3.55

1.764

0.68

0.17

-

227

2826

12.6

37.1

1.7

9106

4117

-

987

51

-

3

377

71

3532

1214

13

-

6.0

17

1391

84.5

-

115

-

778

-

818

756

-

9

--

-

-

-

-

-

25-55

Layer

D1-2E

16.3

16.4

1.0

3.74

1.08

0.99

0.33

0.86

14.6

0.920

4.98

0.30

144

165

2316

10.7

47.2

0.5

5646

1900

30

1249

43

14

5

300

29

3074

998

17

24.8

9.4

12

1537

61.3

6.7

64.5

14.1

589

<4

725

472

<2

6

..

-

55-90

Layer

D1-3A

19.7

20.1

1.0

4.33

1.12

0.93

0.45

0.92

9.85

1.387

3.02

0.28

225

206

2735

11.1

54.8

0.4

7276

3600

190

1324

28

13

2

435

49

2429

1280

14

34.7

9.1

9

1619

100

12.9

75.6

12.7

664

<4

686

534

<2

10

--

-

-

-

-

0-62

Bulk
Table 14 continued

Fe wt%

Mi

Fe/Mn

Si

Na

Al

K

Mg

Ca

Ti

P

S

As ppm

B

Ba

Be

Bi

Cd

a

Co

Cr

Cu

Ga

Hf

Li

Nfo

Nb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

Tl

U

V

W

Zn

Zr

Au ppb

Hg

Ir

Os

Pd

Pt

Rh

Ru

Interval

Type

D2-1C

22.0

29.1

0.9

3.87

1.39

0.71

0.53

1.20

3.27

1.777

0.54

0.25

192

214

2585

10.3

47.5

2.2

11128

6663

<2

1044

66

14

2

511

66

4852

1378

22

26.3

6.5

14

1435

115

<0.6

200

<0.6

700

<5

788

645

<2

<6

--

-

-

-

10-60

Layer

D2-1C1

21.9

29.0

0.9

3.88

1.40

0.72

0.53

1.19

3.25

1.770

0.54

0.22

179

228

2600

11.5

52.0

1.9

10889

6237

<2

1072

54

12

2

486

67

4960

1254

23

25.8

6.2 '

15

1448

119

7.1

187

<0.6

751

<5

745

647

<2

<6

-

-

-

-

-

10-60

Layer

D2-1D

15.5

18.3

0.9

2.08

0.88

0.38

0.18

0.77

15.6

0.904

5.26

0.33

182

163

2284

11.0

73.4

<0.2

6531

2583

<2

975

54

11

3

417

27

2593

1131

13

22.9

10.9

10

1558

77.6

15.7

94

<0.5

687

<4

594

400

<2

6

-

-

-

-

-

60-100

Layer

D2-1E

22.2

26.6

1.0

3.45

1.15

0.52

0.47

0.97

8.41

2.002

2.26

0.33

193

200

5042

18.3

97.7

<0.2

10965

3920

<2

881

66

13

2

667

66

3004

2618

23

39.4

6.9

11

1870

153

16.3

122

12.8

982

<5

764

615

<2

<6

--

-

--

--

-

-

100-150

Layer

D2-2A

17.4

24.9

0.8

2.10

1.06

0.27

0.24

0.93

13.1

1.543

4.06

0.30

211

161

3178

9.8

63.6

<0.2

7765

4889

190

815

29

10

<1

488

49

2678

1676

20

36.1

5.8

12

1665

127

18.6

130

17.9

655

<5

595

418

<2

<6

7

2

7

722

34

16

0-98

Bulk

D2-2B

21.8

34.0

0.8

2.65

1.50

0.18

0.42

1.26

3.54

2.067

0.46

0.23

253

191

2931

8.4

63.9

1.7

11677

9686

191

1198

37

14

<1

484

104

4487

1749

18

43.2

6.6

19

1544

191

17.4

207

<0.6

653

<5

749

655

54

6

17

2

12

1930

84

41

0-30

Layer

D2-2C

16.1

27.3

0.7

1.52

1.01

0.07

0.24

0.94

11.0

1.392

3.16

0.36

-

159

3122

9.4

97.8

<0.2

7911

6033

1052

38

..

<1

657

42 

3322

2022

11

-

7.3

10

1811

159

-

171

-

679

-

699

438

-

7

7

2

4

778

30

13

30-47

Layer

D2-2D

15.8

17.4

1.0

2.03

0.85

0.48

0.17

0.71

16.3

1.559

5.60

0.35

198

147

3376

11.4

86.7

0.8

6160

2923

151

577

29

9

1

399

46

1510

2028

15

39.9

4.5

9

1888

135

10.6

89

<0.5

588

<4

578

334

<2

<5

4

-

4

583

26

9

47-82

Layer

D2-3A

19.2

27.3

0.8

2.47

1.11

0.33

0.34

1.02

11.1

1.309

3.28

0.33

234

173

3464

9.6

63.7

0.6

7734

4270

172

1084

34

10

4

689-

36

3144

1601

18

33.8

7.1

7

1791

84.3

13.5

73

15.1

732

171

745

419

<2

<6

5

-

7

403

19

14

0-110

Bulk

D2-4A

19.7

28.8

0.8

4.26

1.39

0.71

0.52

1.19

3.37

1.640

0.51

0.22

189

231

2127

8.2

47.4

2.7

8059

7061

<2

476

56

6

3

533

46

5493

1568

16

25.3

5.0

9

1327

80.5

<0.6

200

<0.6

692

<4

714

488

<2

9

--

-

-

-

0-25

Bulk

D2-5A

20.1

29.3

0.8

3.99

1.43

0.66

0.55

1.20

2.93

1.591

0.46

0.22

187

236

2215

8.6

44.7

2.2

8350

7353

<2

422

71

<1

2

538

50

5194

1661

18

28.5

4.9

9

1351

76.0

6.1

183

<0.6

715

<4

721

512

<2

9

-

-

--

-

-

0-20

Layer

All Ag contents <0.2ppm; Br <lppm; 

Duplicate analysis of sample

Cs <3ppm; Ge <10ppm; In <0.5ppm; Se <5ppm; Ta <lppm
Table 15 Statistics for 25 bulk Fe-Mn crusts and crust layers from Marshall Islands Fe-Mn crust leg 

KODOS 98-3 cruise; hygroscopic water-free data from Table 14

Fe wt. %

Mn

Fe/Mn4

Si

Na

Al

K

Mg

Ca

Ti

P

SH2O'

LOI

As ppm

B

Ba

Be

Bi

Cd

Cl

Co

Cr

Cu

Ga

Hf

Li

Mo

Nb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

n

u

V

w

Y

Zn

Zr

Au ppb

Hg

Ir

Os

Pd

Pt

Rh

Ru

Depth5

Thickness

N

25

25

25

25

25

25

25

25

25

25

25

25

25

25

20

25

25

25

25

25

25

25

20

25

25

20

25

25

25

25

25

25

20

25

25

25

25

20

25

20

25

20

25

25

25

21

25

10

6

10

10

10

10

25

25

Mean

20.0

24.9

0.8

4.04

1.27

0.78

0.49

1.08

7.53

1.578

2.12

0.26

11.3

17.4

201

204

2865

10.5

54.5

-1.2

8200

5001

-102

911

49

-12

-4

471

53

3535

1513

17

33.0

7.0

11

1536

96.6

-9.7

130

-6.1

697

-23.1

287

708

543

 5

-17

7

2

8

648

31

20

1878

47

Median

20.1

26.3

0.8

3.74

1.31

0.56

0.45

1.11

6.03

1.564

1.80

0.25

10.0

17.7

196

210

2931

10.7

48.8

-0.8

8059

4340

-107

976

51

-13

-2

474

49

3473

1542

16

33.6

6.6

10

1558

84.5

-11.0

126

-0.6

703

 5

271

699

537

 2

-6

5

2

7

523

26

19

1805

35

SD1

2.6

5.4

0.5

2.08

0.22

0.77

0.30

0.19

4.68

0.313

1.75

0.06

3.86

1.70

30

35

795

2.4

19.8

0.9

1571

2179

92

308

19

4

6

130

16

1026

396

6

6.0

1.7

3

258

36.3

6.4

50

7.1

95

47

69

75

114

11

44

4

0.1

4

484

20

9

84

37

Min2

15.5

10.9

1.4

1.52

0.85

0.01

0.17

0.71

2.84

0.904

0.46

0.15

6.30

13.2

138

147

1110

5.8

12.5

<0.2

5646

1900

<2

422

27

<1

<1

109

27

1510

541

8

22.9

4.5

7

597

32.0

<0.5

59

<0.5

448

<4

195

578

334

<2

<5

2

2

4

151

14

9

1805

7

Max3

25.1

34.0

0.7

11.68

1.70

3.94

1.73

1.57

16.27

2.067

5.60

0.36

18.7

20.4

253

270

5042

18.3

97.8

2.7

11677

10711

227

1506

89

18

32

689

104

5493

2618

39

43.2

11.5

19

1888

191

18.6

233

18.6

982

171

393

875

791

54

226

17

2

16

1930

84

41

1970

142

Standard deviation; Minimum; 

depth in meters; 6Crust thickness

Maximum; Ratio of means, 

in millimeters

not a mean of the summation of ratios; JWater

37
Table 16. Statistics for 9 bulk Fe-Mn crusts from Marshall Islands Fe-Mn crust leg KODOS 98-3 

cruise; hygroscopic water-free data from Table 14

Fe wt.%

Mn

Fe/Mn4

Si

Na

Al

K

Mg

Ca

Ti

P

S

H2O

LOI

As ppm

B

Ba

Be

Bi

Cd

Cl

Co

Cr

Cu

Ga

Hf

Li

Mo

Nb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

Tl

U

V

W

Y

Zn

Zr

Au ppb

Hg

IT

Os

Pd

Pt

Rh

Ru

Depth5

Thickness6

N

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

9

4

3

4

4

4

4

9

9

Mean

20.1

25.2

0.8

3.88

1.23

0.73

0.45

1.07

7.93

1.606

2.19

0.26

12.3

17.6

210

202

2990

10.4

51.7

-1.0

8097

4786

-124

967

45

12

-4

485

51

3404

1491

17

33.4

7.2

10

1571

94.7

-10.4

121

-7.5

693

-36

288

712

535

 3

-8

6

2

9

543

26

19

1878

79

Median

19.7

24.9

0.8

4.26

1.25

0.71

0.45

1.07

8.29

1.564

2.42

0.26

12.9

17.7

212

210

3072

10.9

54.8

-0.8

7866

4889

-172

1025

36

13

 3

466

49

3144

1568

17

33.8

7.1

9

1611

84.3

-12.2

129

-0.6

708

 5

304

691

563

 2

-6

6

2

7

523

25

20

1805

95

SD1

1.5

3.1

0.5

1.24

0.12

0.37

0.12

0.12

3.50

0.222

1.24

0.05

4.23

0.9

21

27

603

1.6

11.4

0.8

730

1129

94

288

16

3

2

106

11

893

177

3

4.7

1.3

2

167

25.0

6.1

41

8.3

61

64

58

81

78

3

2

2

0.1

5

136

6

5

87

40

Minz

17.4

20.1

0.9

2.10

1.06

0.27

0.24

0.92

2.84

1.309

0.48

0.20

6.90

16.2

183

161

2044

8.2

28.5

<0.2

7276

3566

<2

476

28

6

<1

354

36

2429

1214

12

25.3

5.0

7

1297

73.5

<0.5

73

<0.5

563

<4

205

595

418

<2

<5

5

2

5

403

19

14

1805

25

Max"

22.1

28.8

0.8

5.80

1.39

1.36

0.62

1.29

13.1

1.896

4.06

0.33

18.7

18.7

237

239

3765

12.4

63.7

2.7

9422

7061

227

1379

73

15

9

689

70

5493

1710

22

41.8

9.1

14

1791

145

18.6

200

18.6

775

171

366

875

636

11

13

9

2

16

722

34

24

1970

142

Standard Deviation; L Minimum; 

depth in meters; 6Crust thickness

""Maximum; "Ratio of means, 

in millimeters

not a mean of the summation of ratios; ''Water

38
Table 17. Statistics for 16 Fe-Mn crust layers from Fe-Mn crust leg KODOS 98-3 cruise; 

hygroscopic water-free data from Table 14

Fe wt. %

Mn

Fe/Mn4

Si

Na

Al

K

Mg

Ca

Ti

P

S

H20

LOI

As ppm

B

Ba

Be

Bi

Cd

Cl

Co

Cr

Cu

Ga

Hf

Li

Mo

Mb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

Tl

U

V

w

Y

Zn

Zr

Au ppb

Hg

Ir

Os

Pd

Pt

Rh

Ru

Depth5

Thickness6

N

16

16

16

16

16

16

16

16

16

16

16

16

16

16

11

16

16

16

16

16

16

16

11

16

16

11

16

16

16

16

16

16

11

16

16

16

16

11

16

11

16

11

16

16

16

12

16

6

3

6

6

6

6

16

16

Mean

19.9

24.7

0.9

4.13

1.30

0.80

0.52

1.08

7.31

1.563

2.08

0.25

10.7

17.4

194

206

2795

10.5

56.1

-1.3

8257

5122

-84

880

52

-12

-4

463

54

3608

1525

17

32.6

7.0

11

1516

97.6

-9.0

135

-4.9

699

-12

286

707

548

-7

-22

7

2

7

719

34

20

1877

29

Median

21.0

26.5

0.8

3.71

1.37

0.54

0.48

1.13

3.70

1.575

0.75

0.24

9.85

17.5

192

207

2706

10.5

47.3

-1.2

8363

4330

-46

976

52

-14

 2

479

50

3502

1536

15

30.0

6.5

10

1540

85.8

-7.9

124

-0.6

702

~5

263

710

525

~2

~8 o

5

2

6

532

26

18

1805

30

SD1

3.1

6.4

0.5

2.47

0.26

0.93

0.37

0.22

5.33

0.360

2.01

0.07

3.64

2.0

35

39

896

2.7

23.5

1.0

1912

2622

91

324

20

4

8

144

19

1116

484

7

7.1

2.0

3

300

42.1

6.8

54

6.2

112

26

76

74

132

15

55

5

0.1

3

629

25

12

85

17

Min^

15.5

10.9

1.4

1.52

0.85

0.01

0.17

0.71

2.90

0.904

0.46

0.15

6.30

13.2

138

147

1110

5.8

12.5

<0.2

5646

1900

<2

422

27

<1

<1

109

27

1510

541

8

22.9

4.5

7

597

32.0

<0.6

59

<0.5

448

<4

195

578

334

<2

<5

2

2

4

151

14

9

1805

7

Max"

25.1

34.0

0.7

11.68

1.70

3.94

1.73

1.57

16.27

2.067

5.60

0.36

17.6

20.4

253

270

5042

18.3

97.8

2.6

11677

10711

221

1506

89

18

32

667

104

5492

2618

39

43.2

11.5

19

1888

191

17.4

233

14.1

982

90

393

818

791

54

226

17

2

12

1930

84

41

1970

65

Standard Deviation; Minimum; 

depth in meters; 6Crust thickness

Maximum; Ratio of means, 

in millimeters

not a mean of the summation of ratios;

39
Table 18. Concentrations of yttrium and rare earth elements (ppm) in Fe-Mn crusts from Marshall 

Islands (Dl, D2) and Fe-Mn crusts and Mn stratabound deposits from FSM (D5-D9), KODOS 98-3 

cruise

Y

La

Ce

Pr

Nd

Sm

Eu

Gd

Tb

Dy

Ho

Er

Tm

Yb

Lu

IREE

Ce*

Interval2

DMA

264

345

1450

54.0

240

43.1

10.1

52.2

7.9

46.2

9.80

29.6

4.3

28.6

4.54

2325

2.3

B 0-85

DMA1

280

359

1510

57.4

247

43.3

10.7

56.4

8.2

47.0

9.94

30.8

4.5

28.5

4.66

2417

2.3

B 0-85

D1-1B

233 '

281

755

44.8

199

37.1

9.80

50.6

7.7

47.5

10.7

32.3

4.8

31.3

4.98

1517

1.5

L 0-7

D1-1C

111

248

841

41.9

179

34.4

8.67

42.2

6.5

36.5

7.79

23.7

3.4

20.3

3.34

1497

1.8

L 7-37

DMD

248

352

1560

55.5

221

40.3

9.51

47.4

7.2

39.9

8.36

24.6

3.8

24.4

3.91

2398

2.4

L 37-102

D1-3A

220

271

1240

46.5

193

36.4

9.28

44.8

6.7

37.6

8.20

23.6

3.5

23.7

3.82

1948

2.5

B 0-62

D1-4A

187

279

1030

48.2

207

40.1

10.3

49.4

7.5

42.5

8.87

25.8

3.7

25.1

3.95

1781

2.0

B 0-45

D2-1C

210

318

1170

52.9

232

43.1

10.1

51.2

8.0

46.3

9.37

29.3

4.2

29.3

4.34

2008

2.0

B 0-9

D2-2A

313

373

1470

52.9

216

37.0

9.04

46.7

7.0

40.8

9.03

27.9

4.0

27.1

4.24

2325

2.2

B 0-98

D2-2B

175

253

1420

39.6

164

30.4

7.63

37.7

5.9

34.1

7.57

22.4

3.3

21.3

3.41

2050

3.1

L 0-30

Y

La

Ce

Pr

Nd

Sm

Eu

Gd

Tb

Dy

Ho

Er

Tm

Yb

Lu

IREE

Ce*

Interval

D2-2C

343

359

1790

57.0

231

40.2

9.68

51.3

7.8

44.3

9.66

30.0

4.5

30.0

4.43

2669

2.7

L 30-47

D2-2D

344

398

1750

52.2

208

32.5

8.16

45.9

6.6

37.6

8.96

26.9

3.7

24.6

4.19

2607

2.6

L 47-82

D2-3A

256

333

1230

56.2

233

41.1

9.96

50.8

7.6

43.1

9.44

27.8

4.0

27.2

4.06

2077

2.0

B 0-110

D2-6A

319

273

710

46.7

209

40.5

10.6

53.7

8.0

47.0

10.4

30.2

4.1

26.7

4.59

1474

1.4

B 0-32

D5-2A

204

299

718

62.1

258

53.8

13.0

61.9

9.4

50.4

10.2

28.8

3.6

27.6

4.10

1600

1.2

B 0-8

D5-2A1

192

298

663

58.8

247

51.3

12.6

58.9

9.0

48.1

9.54

28.0

3.9

25.8

3.90

1518

1.1

B 0-8

D5-16A

24

23.1

55.1

5.1

21.5

4.8

1.30

5.8

0.9

4.9

1.10

3.0

0.4

2.0

0.51

130

1.2

Mn SS

D7-11A

207

290

594

58.8

247

52.9

11.1

58.6

9.1

50.2

10.1

27.9

3.4

30.5

4.06

1448

1.0

B 0-5

D8-1A

10

9.4

6.3

1.7

7.1

1.9

0.86

2.1

0.3

1.7

0.44

1.3

0.2

0.6

0.22

34

0.4

Strat. Mn

D9-5-1A

224

307

673

63.9

271

55.6

13.6

65.4

9.8

54.1

11.0

31

3.7

32.2

4.47

1596

1.1

B 0-5

Duplicate analysis of sample

Intervals measured from the outer surface of the crust; B = bulk, L = layer; Ce* = 2Ce/La+Pr from chondrite-normalized data

40
Table 19. Correlation coefficient matrix for 9 bulk crusts listed in Table 14; n=9, except for Cd, Li = 8; Th = 7; Cr, Hg = 6; Ir, Pd, 

correlations for 9 points, 8 points, 7 points, 6 points, and 4 points at the 95% confidence level are 10.6651, 10.7061, 10.7531, 10.81

statistically significant correlations are in bold; -- = insufficient correlation pairs

Mi

Fe/Mn

Si

Na

Al

K

Mg

Ca

Ti

P

S

LOI

As

B

Ba

Be

Bi

Cd

a

Co

Cr

Cu

Ga

Hf

Li

Mo

Mb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

Tl

U

V

Y

Zn

Zr

Hg

Ir

Pd

Pt

Rh

Ru

Depth

Thick

Fe

0.25

0.161

0.509

0.66

0.363

0.633

0.62

-0.602

0.636

-0.62

-0.558

0.369

0.097

0.539

0.095

0.311

-0.439

-0.062

0.511

0.015

0.202

0.258

0.535

0.384

0.393

-0.117

0.44

0.184

-0.083

-0.104

0.281

0.38

-0.057

-0.211

-0.252

-0.762

0.037

0.025

0.211

-0.151

0.335

0.858

-0.085

-0.042

0.197

-0.442

-0.448

0.858

0.342

-0.081

Mn

-0.812

-0.371

0.507

-0.537

-0.167

0.404

-0.193

0.269

-0.243

-0.144

0.889

0.057

-0.072

0.267

-0.17

0.252

0.305

0.39

0.529

0.362

-0.283

0.563

-0.555

0.143

0.673

-0.07

0.548

0.821

0.321

0.044

-0.624

-0.039

-0.017

0.085

0.132

0.403

0.564

0.388

0.145

-0.117

-0.15

-0.168

-0.957

-0.818

-0.213

-0.328

-0.015

-0.471

0.177

Fe/Mn

0.751

0

0.853

0.546

0.109

-0.208

0.065

-0.174

-0.3

-0.68

0.081

0.371

-0.564

-0.116

-0.664

-0.02

-0.046

-0.255

-0.488

0.145

-0.536

0.593

0.271

-0.717

0.273

-0.259

-0.839

-0.132

0.048

0.757

-0.144

-0.341

-0.331

-0.613

-0.231

-0.543

-0.605

-0.131

0.22

0.412

0.584

0.87

0.982

-0.297

-0.187

0.501

0.365

-0.527

S

0.546

0.968

0.953

0.615

-0.777

0.468

-0.76

-0.837

-0.417

-0.193

0.801

-0.697

-0.231

-0.944

0.483

0.257

0.234

-0.445

-0.19

-0.143

0.456

0.368

-0.695

0.425

0.342

-0.679

-0.251

-0.218

0.389

-0.026

-0.664

-0.534

-0.842

0.289

0.022

-0.414

-0.375

0.533

0.692

0.465

0.718

0.882

-0.376

-0.286

0.703

0.309

-0.752

Na

0.403

0.643

0.929

-0.76

0.761

-0.796

-0.847

0.445

-0.217

0.539

-0.437

-0.343

-0.631

0.712

0.705

0.702

-0.134

-0.499

0.391

-0.03

0.562

-0.18

0.501

0.728

0.168

0.231

-0.091

-0.198

0.033

-0.748

-0.207

-0.671

0.678

0.621

-0.217

-0.014

0.088

0.505

0.303

0.522

0.643

-0.228

-0.169

0.924

-0.239

-0.478

Al

0.871

0.509

-0.608

0.408

-0.586

-0.714

-0.527

-0.202

0.648

-0.716

-0.248

-0.932

0.36

0.24

0.142

-0.569

-0.198

-0.322

0.567

0.407

-0.799

0.461

0.181

-0.739

-0.172

-0.19

0.456

0.016

-0.641

-0.45

-0.755

0.201

-0.001

-0.566

-0.247

0.441

0.608

0.519

0.845

0.961

-0.295

-0.19

0.574

0.254

-0.704

K

0.714

-0.871

0.549

-0.864

-0.892

-0.266

-0.295

0.848

-0.563

-0.134

-0.899

0.558

0.345

0.302

-0.371

-0.22

0.093

0.418

0.339

-0.583

0.429

0.481

-0.559

-0.317

-0.297

0.248

0.018

-0.638

-0.548

-0.883

0.375

0.171

-0.201

-0.436

0.634

0.763

0.146

0.561

0.783

-0.487

-0.415

0.753

0.299

-0.64

Mg

-0.721

0.634

-0.758

-0.832

0.334

-0.216

0.495

-0.498

-0.441

-0.745

0.763

0.684

0.596

-0.351

-0.531

0.295

0.06

0.764

-0.202

0.411

0.679

0

0.317

-0.146

-0.084

-0.148

-0.756

-0.392

-0.748

0.541

0.523

-0.308

0.089

0.169

0.456

0.416

0.561

0.783

-0.487

-0.415

0.753

-0.299

-0.476

Ca

-0.525

0.997

0.954

0.008

0.169

-0.934

0.505

0.249

0.741

-0.718

-0.244

-0.527

0.117

0.275

-0.251

-0.003

-0.131

0.262

-0.217

-0.717

0.265

0.325

0.269

0.058

0.02

0.562

0.589

0.81

-0.563

-0.364

-0.029

0.542

-0.644

-0.619

0.01

-0.3

-0.514

0.419

0.383

-0.897

-0.257

0.72

Ti

-0.542

-0.631

0.383

-0.324

0.32

-0.142

0.06

-0.49

0.213

0.86

0.517

-0.207

-0.322

0.22

0.46

0.411

-0.443

0.883

0.368

0.225

0.051

0.037

-0.119

0.583

-0.537

0.238

-0.353

0.588

0.721

-0.192

0

0.12

0.677

-0.158

0.753

0.699

0.139

0.218

0.85

-0.106

-0.165

P

0.958

-0.039

0.187

-0.915

0.501

0.26

0.732

-0.751

-0.287

-0.556

0.117

0.304

-0.291

0.016

-0.166

0.237

-0.23

-0.747

0.224

0.287

0.279

0.084

0.03

0.586

0.572

0.824

-0.584

-0.364

-0.027

0.514

-0.61

-0.61

-0.01

-0.289

-0.511

0.438

0.403

-0.889

-0.209

0.699

S

0.005

0.253

-0.844

0.647

0.381

0.865

-0.785

-0.407

-0.611

0.285

0.448

-0.154

-0.085

-0.376

0.423

-0.378

-0.714

0.26

0.113

0.259

0.062

-0.027

0.745

0.513

0.788

-0.647

-0.478

0.237

0.335

-0.477

-0.603

-0.227

-0.636

-0.76

0.256

0.181

-0.854

-0.082

0.769

LOI

0.262

-0.269

0.445

-0.002

0.281

0.025

0.525

0.287

0.436

-0.053

0.478

-0.28

0.345

0.585

0.117

0.195

0.848

0.512

0.429

-0.346

0.012

0.11

0.255

0.123

0.159

0.612

0.276

0.427

-0.29

-0.027

-0.069

-0.812

-0.738

-0.04

-0.145

0.308

-0.424

0.355

As

-0.112

0.27

-0.078

0.18

-0.334

-0.33

-0.435

0.566

0.624

-0.258

-0.164

0.151

0.504

-0.464

-0.456

0.048

0.251

0.789

0.487

-0.555

0.555

-0.295

-0.209

-0.641

-0.749

0.119

0.208

0.021

-0.145

0.475

-0.888

-0.635

-0.478

-0.578

0.031

0.215

-0.013

B

-0.48

-0.092

-0.691

0.548

-0.039

0.274

0.038

-0.044

0.209

0.042

-0.134

-0.337

0.081

0.526

-0.511

-0.524

-0.248

0.142

-0.096

-0.427

-0.659

-0.781

0.362

0.117

0.096

-0.683

0.689

0.651

-0.044

0.176

0.36

-0.331

-0.314

0.938

0.537

-0.727

Ba

0.754

0.75

-0.781

-0.107

-0.549

0.742

0.64

0.405

0.065

-0.351

0.513

-0.162

-0.526

0.446

-0.091

0.463

0.022

0.145

0.831

0.392

0.479

-0.509

0.256

0.736

0.162

-0.094

-0.026

-0.793

-0.96

-0.984

0.135

0.014

-0.263

0.223

0.884

Be

0.422

-0.793

-0.085

-0.609

0.846

0.685

0.457

0.441

-0.521

-0.049

0.172

-0.51

-0.03

-0.492

0.232

0.282

0.351

0.534

0.368

0.194

-0.407

-0.229

0.621

-0.187

0.071

0.44

-0.729

-0.781

-0.848

0.272

0.164

0.22

0.605

0.677

Bi

-0.613

-0.352

-0.329

0.524

0.364

0.163

-0.372

-0.594

0.662

-0.409

-0.386

0.568

-0.03

0.154

-0.28

0.092

0.739

0.566

0.796

-0.358

-0.303

0.55

0.113

-0.402

-0.579

-0.542

-0.803

-0.922

0.287

0.188

-0.664

-0.096

0.768

Cd

0.199

0.793

-0.522

-0.833

0.051

-0.481

0.346

-0.144

0.008

0.865

0.001

0.277

-0.47

-0.53

-0.17

-0.795

-0.453

-0.922

0.763

0.997

-0.42

-0.042

0.015

-0.1

0.436

0.99

0.951

0.132

0.376

0.545

-0.436

-0.739

a

0.512

-0.544

-0.453

0.187

0.399

0.642

-0.253

0.831

0.339

0.385

0.384

-0.006

-0.158

0.407

-0.554

0.346

-0.283

0.478

0.881

-0.329

0.313

-0.146

0.394

0.073

0.854

0.961

-0.276

-0.17

0.576

-0.501

0.05
Table 19 continued

K)

Mo

Nb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

Tl

U

V

Y

Zn

Zr

Hg

Ir

Pd

Pt

Rh

Ru

Depth

Thick

Li

-0.195

0.373

0.073

0.063

0.874

0.33

0.207

-0.245

-0.487

-0.172

-0.688

0.088

0.404

-0.69

0.803

-0.304

0.142

0.673

1

0.985

-0.011

0.24

0.419

-0.539

-0.227

Mo

-0.658

0.048

0.601

0.175

0.207

-0.291

-0.422

0.568

-0.034

0.291

-0.255

-0.189

0.578

0.082

-0.094

-0.542

-0.237

-0.964

-0.811

-0.299

-0.406

-0.484

-0.23

0.376

Nb

0.107

0.07

0.05

-0.039

0.039

0.681

-0.54

0.473

-0.204

0.427

0.507

-0.398

0.092

-0.08

0.593

-0.089

0.95

0.843

0.206

0.312

0.571

-0.142

-0.015

Ni

0.198

-0.075

-0.636

-0.628

0.045

-0.669

-0.255

-0.527

0.849

0.657

-0.017

-0.374

0.256

0.061

0.004

0.48

0.803

-0.748

-0.675

0.446

-0.354

-0.522

Pb

0.398

0.162

-0.663

0.293

0.175

0.581

0.677

0.296

0.599

0.256

0.341

-0.426

-0.378

-0.279

-0.683

-0.891

0.485

0.396

-0.63

-0.594

0.456

Rb

0.414

-0.058

-0.309

-0.193

0.114

0.108

-0.022

0.067

-0.526

0.921

-0.684

-0.354

0.765

1

0.901

0.147

0.265

0.296

-0.699

0.081

Sb

0.506

-0.223

0.479

0.031

-0.077

-0.571

0.042

0.051

0.517

-0.247

0.147

0.328

-0.342

-0.435

0.34

0.279

0.7

0.233

0.245

Sc

-0.392

0.18

-0.311

-0.725

-0.73

-0.823

-0.171

0.049

0.139

0.438

0.39

0.215

0.519

-0.636

-0.603

0.759

0.556

-0.052

Sn

-0.104

0.7

0.401

0.474

0.805

0.01

-0.169

0.025

0.225

-0.818

0.35

-0.065

0.877

0.903

-0.33

-0.043

0.21

Sr

0.118

0.48

-0.729

-0.229

0.653

0.026

0.066

-0.274

-0.654

-0.945

-0.954

0.067

-0.046

-0.527

0.369

0.634

Te

0.744

0.119

0.183

-0.037

0.26

-0.587

-0.199

-0.362

0.023

-0.36

0.814

0.804

-0.565

-0.35

0.605

Th

0.049

0.237

0.161

0.271

-0.574

-0.691

-0.602

-0.26

-0.594

0.721

0.679

-0.661

-0.34

0.617

Tl

0.918

-0.207

-0.222

0.045

0.097

-0.115

0.878

0.585

0.602

0.694

0.22

-0.399

-0.446

U

0.212

0.126

0.266

0.185

-1

1

1

1

1

-0.181

-0.097

V

-0.42

0.356

0.092

-0.94

-0.982

-0.91

-0.069

-0.189

-0.128

0.452

0.481

Y

-0.715

-0.295

0.579

0.903

0.627

0.556

0.652

0.208

-0.541

0.353

Zn

0.442

-0.514

-0.389

0.048

-0.963

-0.987

0.014

0.522

-0.362

Zr Hg Ir 

-0.366

0.25

0.357 - 0.901

-0.157 - 0.147 

-0.135 - 0.265 

0.986 - 0.296 

0.576 -0.418 -0.522 

-0.18 -0.539 -0.906 
Table 20. Correlation coefficient matrix for 5 bulk crusts >85mm listed in Table 14; n=5, except for Cd, Li, and Th = 4; t

correlations for 5 and 4 points at the 95% confidence level are 10.8831 and 10.9621, respectively; statistically significant co

bold; - = insufficient correlation pairs

Mn 

FeMn 

S 

Na 

Al 

K 

Mg 

Ca 

Ti 

P 

S 

LOI 

As 

B 

Ba 

Be 

Bi

Cd

a

Co

Cu

Ga

Hf

Li

Mo

Nb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

TI

V

Y

Zn

Zr

Depth

Thick

Fe

0.511 

-0.116 

0.486 

0.882 

0.141 

0.629 

0.982 

-0.83 

0.548 

-0.877 

-0.803 

0.493 

0.082 

0.624 

0.8 

0.772 

-0.346

-0.066

0.44

-0.216

0.669

0.95

0.278

0.482

0.13

0.286

0.634

0.026

-0.231

0.306

0.667

-0.209

-0.164

-0.156

-0.842

-0.128

0.806

-0.346

0.193

0.85

0.458

0.393

Mn

-0.896

-0.495 

0.649 

-0.768 

-0.32 

0.522 

-0.049 

0.395 

-0.118 

0.041 

0.981 

0.612 

-0.221 

0.919 

-0.04 

0.613

-0.628

0.508

0.355

0.378

0.301

-0.373

0.989

0.731

0.101

0.317

0.792

0.659

0.696

0.05

-0.197

0.288

0.2

-0.984

-0.119

0.343

0.453

-0.339

0.039

-0.328

0.471

Fe/Mn

0.808 

-0.408 

0.943

0.686 

-0.134 

-0.366 

-0.34 

-0.306 

-0.389 

-0.92 

-0.566 

0.582 

-0.665 

0.332 

-0.867

0.73

-0.472

-0.616

-0.028

0.06

0.494

-1

-0.65

-0.132

-0.044

-0.96

-0.907

-0.672

0.364

-0.035

-0.264

-0.448

-

-0.104

0.087

-0.776

0.639

0.298

0.612

-0.406

S

0.184 

0.926 

0.977

0.467 

-0.79 

0.082 

-0.769 

-0.816 

-0.518 

-0.509 

0.853 

-0.125 

0.778 

-0.963

0.739

-0.1

-0.614

0.315

0.62

0.652

-0.877

-0.545

0.124

0.363

-0.805

-0.936

-0.441

0.667

-0.081

-0.398

-0.419

-0.777

-0.094

0.509

-0.874

0.632

0.78

0.779

-0.075

Na

-0.11 

0.32 

0.873 

-0.541 

0.833 

-0.605 

-0.634 

0.704 

0.014 

0.299 

0.827 

0.715 

-0.057

-0.316

0.7

0.198

0.387

0.862

0.257

0.577

0.042

0.576

0.548

0.396

0.106

0.436

0.264

0.149

-0.354

0.271

-0.564

0.26

0.468

0.063

-0.289

0.747

0.167

0.568

Al

0.845 

0.144 

-0.509 

-0.026 

-0.472 

-0.584 

-0.775 

-0.708 

0.649 

-0.479 

0.613 

-0.924

0.625

-0.181

-0.497

-0.016

0.32

0.718

-0.951

-0.742

0.15

0.216

-0.868

-0.962

-0.68

0.395

0.121

-0.501

-0.287

-0.365

0.069

0.171

-0.826

0.559

0.557

0.623

-0.141

K

0.629 

-0.84 

0.171 

-0.836 

-0.838 

-0.361 

-0.449 

0.841 

0.054 

0.824 

-0.89

0.671

0.037

-0.558

0.385

0.71

0.669

-0.816

-0.419

0.173

0.529

-0.697

-0.898

-0.394

0.719

-0.117

-0.384

-0.392

-0.831

-0.13

0.617

-0.889

0.644

0.832

0.721

0.08

Mg

-0.754 

0.597 

-0.812 

-0.727 

0.492 

-0.007 

0.524 

0.785 

0.769 

-0.286

-0.316

0.556

-0.102

0.555

0.903

0.384

0.577

0.123

0.377

0.768

0.076

-0.254

0.181

0.591

-0.123

-0.242

-0.055

-0.831

-0.067

0.747

-0.383

0.194

0.815

0.327

0.542

Ca

-0.151 

0.996 

0.94

-0.017 

-0.034 

-0.953

-0.434 

-0.75 

0.753

-0.749

0.067

0.69

-0.792

-0.881

-0.238

0.279

0.068

0.051

-0.328

0.5

0.57

-0.16

-0.909

0.433

0.035

0.572

0.862

0.366

-0.881

0.625

-0.537

-0.865

-0.863

0.101

Ti

-0.218 

-0.387 

0.503 

-0.418 

-0.052 

0.465 

0.674 

0.047

-0.483

0.902

0.592

-0.18

0.592

0.541

0.378

-0.331

0.924

0.547

0.485

0.109

0.089

-0.225

0.67

-0.749

0.718

-0.043

0.739

-0.053

0.19

-0.578

0.586

-0.159

0.76

P

0.937

-0.085 

-0.03 

-0.921

-0.497 

-0.775 

0.709

-0.662

-0.019

0.628

-0.783

-0.91

-0.266

0.184

0.041

-0.007

-0.402

0.433

0.543

-0.167

-0.893

0.404

0.064

0.517

0.873

0.336

-0.89

0.611

-0.506

-0.884

-0.813

0.012

S

0.011 

0.203 

-0.9 

-0.346 

-0.897 

0.793

-0.592

-0.089

0.512

-0.592

-0.932

-0.41

0.309

0.345

-0.223

-0.31

0.445

0.562

-0.108

-0.717

0.123

0.324

0.32

0.645

0.039

-0.68

0.52

-0.298

-0.966

-0.833

0.011

LOI

0.548 

-0.246 

0.896

0.01 

0.613

-0.603

0.559

0.433

0.308

0.327

-0.351

0.967

0.618

0.209

0.249

0.843

0.715

0.741

-0.047

-0.066

0.183

0.313

-0.822

0.032

0.246

0.56

-0.493

0.077

-0.329

0.472

As

-0.026 

0.521 

-0.524 

0.447

0.018

-0.366

-0.257

0.634

-0.083

-0.915

0.577

0.897

-0.699

-0.356

0.32

0.597

0.798

0.292

-0.768

0.913

-0.462

-0.419

-0.7

0.409

0.386

0.05

-0.339

0.014

-0.366

B

0.166 

0.659 

-0.881

0.925

-0.316

-0.834

0.73

0.735

0.203

-0.56

-0.205

-0.193

0.109

-0.711

-0.673

0.059

0.894

-0.456

0.002

-0.689

-0.795

-0.401

0.777

-0.674

0.615

0.773

0.969

-0.349

Ba

0.294 

0.252

-0.432

0.479

0.085

0.621

0.637

-0.198

0.904

0.595

0.127

0.444

0.532

0.363

0.67

0.378

-0.297

0.191

0.001

-0.931

-0.2

0.635

0.165

-0.123

0.401

0.03

0.426

Be

-0.68

0.189

0.454

-0.146

0.243

0.892

0.727

-0.239

-0.529

0.606

0.574

-0.273

-0.575

-0.144

0.432

0.263

-0.676

0.068

-0.466

0.315

0.436

-0.496

0.111

0.976

0.542

0.368

Bi

-0.853

0.303

0.711

-0.327

-0.534

-0.505

0.876

0.595

0.007

-0.099

0.881

0.887

0.355

-0.642

0.123

0.31

0.5

0.646

0.119

-0.435

0.779

-0.589

-0.703

-0.873

0.317

C

-0.

-0.

0.5

0.2

-0.

-0

-0.

-0.

-0

-0.

-0.

0.0

0.

-0.

0.

-0.

-0.

-0.

0.5

-0.

0.

0.

0.9

-0
Table 20 continued

Ga

Hf

Li

Mo

Mb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Th

Tl

V

Y

Zn

Zr

Depth

Thick

Cu

0.607

-0.377

0.212

0.493

-0.499

0.024

-0.228

-0.102

0.585

0.894

-0.825

0.548

-0.756

-0.83

-0.737

0.932

-0.276

0.483

0.445

0.688

-0.33

Ga

0.368

0.131

-0.137

0.36

0.494

-0.118

-0.334

0.263

0.639

-0.08

-0.318

-0.136

-0.692

0.018

0.715

-0.355

0.13

0.958

0.616

0.263

Hf

-0.444

-0.721

0.736

0.68

-0.295

-0.69

-0.741

-0.017

0.607

-0.887

0.36

-0.048

0.544

-0.066

-0.576

0.125

0.571

0.073

0.567

Li

0.729

0.137

0.378

0.961

0.98

0.656

-0.279

-0.077

0.267

0.389

-

-0.008

0.217

0.979

-0.682

-0.19

-0.577

0.529

MD

-0.556

0.006

0.444

0.548

0.571

0.221

-0.688

0.824

-0.315

-0.592

-0.674

0.399

0.262

0.129

-0.394

-0.257

-0.012

Mb

0.549

0.358

-0.046

-0.26

-0.423

0.872

-0.918

0.831

0.198

0.887

-0.317

0.093

-0.545

0.448

-0.288

0.784

Ni

0.112

-0.364

-0.365

0.218

0.183

-0.453

0.236

-0.562

0.132

0.36

-0.492

0.227

0.498

-0.135

0.844

Pb

0.872

0.493

-0.569

0.308

0.019

0.68

0.646

0.359

-0.3

0.799

-0.772

-0.3

-0.745

0.553

Rb

0.698

-0.531

0.051

0.368

0.406

0.766

0.124

-0.336

0.948

-0.736

-0.537

-0.6

0.075

Sb

0.165

-0.395

0.518

-0.131

-0.294

-0.247

0.321

0.614

-0.378

0.02

0.122

-0.225

Sc

-0.748

0.329

-0.831

-0.939

-0.715

0.953

-0.675

0.769

0.586

0.814

-0.286

Sn

-0.87

0.904

0.643

0.985

-0.728

0.273

-0.665

0.07

-0.454

0.54

Sr

-0.661

-0.279

-0.857

0.345

0.164

0.325

-0.505

0.065

-0.569

Te

0.626

0.904

-0.693

0.533

-0.822

-0.1

-0.714

0.696

Th

0.62

-0.971

0.878

-0.799

-0.592

-0.603

-0.167

Tl V

-0.678

0.355 -0.532

-0.745 0.629

0.143 0.594

-0.387 0.657

0.509 -0.074

Y 

-0.877

-0.492 

-0.554 

0.011 
Table 21. Correlation coefficient matrix for 4 bulk crusts <62mm listed in Table 14; n=4; the zero correlation for 4 points 

confidence level is 10.9621; statistically significant correlations are in bold

Mi

Fe/Mn

Si

Na

Al

K

Mj

Ca

Ti

P

S

LOI

As

B

Ba

Be

Bi

Cd

a

Co

Cu

Ga

Hf

Li

Ma

Nb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Tl

V

Y

Zn

Zr

Hg

Depth

Thick

Fe

-0.011

0.26

0.932

0.379

0.828

0.901

0.46

-0.455

0.925

-0.419

-0.575

0.448

0.192

0.285

0.165

0.028

-0.779

-0.091

0.775

0.012

-0.026

-0.372

0.74

0.557

-0.724

0.969

-0.122

-0.079

0.177

0.531

0.196

0.499

-0.042

-0.489

0.034

-0.196

0.314

0.593

0.923

-0.18

0.066

-0.146

Mi

-0.91

-0.06

0.808

-0.348

0.4

0.633

-0.857

0.368

-0.89

-0.795

0.866

-0.976

0.727

-0.437

-0.63

-0.183

0.872

0.359

0.996

-0.871

0.93

-0.68

0.007

0.603

-0.191

0.993

0.969

0.052

-0.847

-0.966

0.149

-0.602

-0.627

0.999

0.298

-0.196

0.228

-0.268

-0.255

-0.604

-0.871

Fe/Mn

0.406

-0.492

0.67

-0.091

-0.255

0.737

-0.118

0.753

0.522

-0.608

0.895

-0.794

0.145

0.323

-0.226

-0.655

0.037

-0.872

0.622

-0.96

0.795

0.408

-0.844

0.472

-0.915

-0.977

0.322

0.935

0.985

-0.293

0.272

0.248

-0.906

-0.629

0.564

-0.313

0.379

0.501

0.302

0.599

S

0.471

0.949

0.87

0.618

-0.302

0.827

-0.292

-0.556

0.446

0.185

0.007

-0.141

-0.22

-0.931

0.044

0.888

-0.007

-0.156

-0.419

0.715

0.816

-0.83

0.974

-0.145

-0.207

0.514

0.573

0.296

0.153

-0.294

-0.64

-0.027

-0.532

0.635

0.266

0.772

0.185

-0.192

-0.26

Na

0.237

0.739

0.966

-0.775

0.638

-0.82

-0.943

0.967

-0.771

0.427

-0.683

-0.845

-0.715

0.887

0.82

0.853

-0.935

0.58

-0.276

0.589

0.054

0.297

0.781

0.652

0.546

-0.438

-0.628

-0.062

-0.858

-0.965

0.814

-0.247

0.374

0.075

0.015

0.143

-0.816

-0.971

Al

0.67

0.441

0.015

0.617

0.024

-0.279

0.166

0.436

-0.289

-0.112

-0.11

-0.847

-0.155

0.747

-0.288

0.054

-0.653

0.83

0.828

-0.957

0.939

-0.414

-0.5

0.568

0.769

0.57

-0.021

-0.187

-0.46

-0.321

-0.681

0.741

0.067

0.723

0.363

-0.097

-0.034

K

0.764

-0.732

0.981

-0.723

-0.87

0.79

-0.244

0.468

-0.157

-0.344

-0.866

0.345

0.923

0.432

-0.452

0.035

0.387

0.625

-0.458

0.823

0.305

0.292

0.322

0.147

-0.193

0.391

-0.399

-0.786

0.437

-0.189

0.336

0.521

0.685

-0.132

-0.302

-0.556

Mg

-0.622

0.638

-0.67

-0.878

0.886

-0.606

0.213

-0.748

-0.868

-0.849

0.812

0.909

0.695

-0.87

0.375

-0.103

0.777

-0.17

0.437

0.607

0.434

0.723

-0.23

-0.412

-0.198

-0.896

-0.999

0.637

-0.479

0.596

-0.053

0.084

0.34

-0.845

-0.912

Ca

-0.757

0.996

0.916

-0.911

0.727

-0.897

0.104

0.359

0.387

-0.603

-0.556

-0.845

0.655

-0.644

0.238

-0.08

-0.261

-0.247

-0.789

-0.852

0.091

0.507

0.783

-0.55

0.361

0.635

-0.883

-0.374

0.23

-0.643

-0.261

0.514

0.314

0.715

Ti

-0.733

-0.827

0.735

-0.186

0.568

0.028

-0.176

-0.766

0.223

0.832

0.384

-0.332

0.009

0.431

0.481

-0.428

0.82

0.26

0.304

0.139

0.168

-0.192

0.559

-0.23

-0.664

0.41

-0.026

0.175

0.673

0.769

-0.307

-0.13

-0.444

P

0.933

-0.937

0.774

-0.867

0.187

0.435

0.408

-0.669

-0.577

-0.883

0.717

-0.683

0.288

-0.119

-0.282

-0.219

-0.829

-0.869

0.026

0.546

0.808

-0.477

0.436

0.68

-0.912

-0.324

0.182

-0.575

-0.2

0.449

0.392

0.772

S

-0.989

0.69

-0.645

0.401

0.618

0.701

-0.726

-0.826

-0.819

0.795

-0.516

0.117

-0.469

-0.002

-0.441

-0.733

-0.69

-0.309

0.352

0.629

-0.269

0.639

0.888

-0.816

0.031

-0.181

-0.401

-0.277

0.151

0.577

0.861

LOI

-0.787

0.639

-0.483

-0.692

-0.635

0.815

0.771

0.891

-0.869

0.625

-0.259

0.427

0.124

0.312

0.819

0.76

0.323

-0.475

-0.715

0.188

-0.703

-0.89

0.881

-0.017

0.159

0.316

0.132

-0.114

-0.655

-0.919

As

-0.584

0.56

0.711

0.107

-0.923

-0.27

-0.979

0.902

-0.965

0.8

-0.003

-0.677

0.341

-0.995

-0.931

-0.134

0.91

0.955

0.045

0.673

0.593-

-0.964

-0.216

0.139

-0.024

0.462

0.104

0.694

0.877

B

0.279

0.03

0.009

0.311

0.171

0.677

-0.34

0.614

-0.266

-0.348

0.445

0.038

0.659

0.832

-0.52

-0.526

-0.761

0.785

0.043

-0.228

0.755

0.741

-0.629

0.819

0.252

-0.829

0.072

-0.389

Ba

0.966

0.483

-0.821

-0.487

-0.509

0.808

-0.402

0.435

-0.649

-0.069

0.086

-0.495

-0.224

-0.864

0.364

0.29

0.769

0.961

0.726

-0.407

0.666

-0.687

0.677

0.517

-0.758

0.977

0.769

Be

0.561

-0.926

-0.608

-0.695

0.928

-0.539

0.463

-0.637

-0.124

0.008

-0.666

-0.428

-0.791

0.467

0.471

0.578

0.997

0.851

-0.609

0.533

-0.591

0.466

0.41

-0.58

0.999

0.908

Bi

-0.383

-0.981

-0.252

0.479

0.155

-0.434

-0.932

0.659

-0.823

-0. 124

0.018

-0.735

-0.313

-0.077

0.09

0.623

0.861

-0.203

0.654

-0.762

-0.048

-0.5

-0.377

0.538

0.559

C

0.4

0.9

-0.9

0.8

-0.6

0.3

0.4

-0.1

0.8

0.7

0.5

-0.7

-0.7

-0.3

-0.9

-0.7

0.8

-0.1

0.2

-0

-0.4

0.

-0.9

-0.9
Table 21 continued

Ga

Hf

Li

Nfo

Nb

Ni

Pb

Rb

Sb

Sc

Sn

Sr

Te

Tl

V

Y

Zn

Zr

Hg

Depth

Thick

Cu

-0.762

0.578

-0.432

-0.328

0.047

-0.885

-0.725

-0.532

0.67

0.745

0.269

0.916

0.858

-0.859

0.204

-0.295

0.156

0.34

-0.236

0.913

0.993

Ga

-0.896

-0.254

0.845

-0.539

0.959

0.942

-0.086

-0.983

-0.977

0.018

-0.486

-0.36

0.914

0.413

-0.361

0.051

-0.562

-0.238

-0.527

-0.72

Hf

0.384

-0.927

0.834

-0.758

-0.704

0.072

0.956

0.788

0.285

0.393

0.077

-0.646

-0.322

0.34

0.299

0.863

0.018

0.473

0.489

Li

-0.686

0.679

-0.014

-0.229

0.916

0.369

0.248

-0.428

-0.693

-0.779

0.011

-0.882

0.944

-0.306

0.273

0.685

-0.631

-0.48

Mo

-0.868

0.66

0.716

-0.44

-0.92

-0.779

0.029

-0.049

0.188

0.579

0.645

-0.667

-0.021

-0.721

-0.355

-0.129

-0.25

Nb

-0.288

-0.292

0.331

0.683

0.394

0.31

-0.069

-0.463

-0.151

-0.404

0.498

0.401

0.892

0.035

0.036

-0.065

Ni

0.958

0.08

-0.894

-0.97

0.051

-0.631

-0.597

0.985

0.272

-0.184

0.123

-0.381

-0.186

-0.645

-0.87

Pb

-0.196

-0.881

-0.992

0.313

-0.39

-0.43

0.971

0.524

-0.432

0.363

-0.255

-0.46

-0.4

-0.722

Rb

0.148

0.163

-0.741

-0.823

-0.711

0.035

-0.937

0.959

-0.639

-0.131

0.887

-0.802

-0.531

Sb

0.933

0.048

0.404

0.212

-0.825

-0.448

0.423

0.039

0.678

0.217

0.462

0.609

Sc

-0.208

0.426

0.403

-0.961

-0.495

0.417

-0.251

0.376

0.386

0.449

0.727

Sn

0.566

0.17

0.193

0.745

-0.666

0.989

0.664

-0.939

0.617

0.19

Sr

0.88

-0.583

0.575

-0.638

0.448

0.344

-0.595

0.994

0.903

Te

-0.633

0.47

-0.59

0.024

-0.117

-0.32

0.826

0.903

Tl V

0.313

-0.206 -0.988

0.274 0.673

-0.219 0.009

-0.287 -0.928

-0.58 0.551

-0.865 0.206

Y Zn 

-0.575

0.074 0.707

0.876 -0.898 

-0.602 0.51 

-0.311 0.068 
Table 22. Chemical composition of Fe-Mn oxyhydroxide crusts and stratabound Mn 

deposits from FSM hydrothermal leg, KODOS 98-3 cruise

Fe wt.%

Mn

Fe/Mn

Si

Na

Al

K

Mg

Ca

Ti

P

S

H2O

LOI

B ppm

Ba

Be

Bi

Cd

Cl

Co

Cu

Ga

Li

Mo

Nb

Ni

Pb

Rb

Sc

Sn

Sr

Te

Tl

V

Zn

Zr

Hg ppb

Interval

Type

D5-2A

19.0

21.1

0.9

6.40

1.19

1.49

0.48

1.50

3.22

0.933

0.41

0.17

7.70

17.2

213

1420

6.2

11.1

1.8

9090

3700

763

51

8

364

44

3530

1080

19

10.8

6

1160

39.5

117

531

619

480

15

0-8

Bulk

D5-2A1

19.0

21.1

0.9

6.40

1.19

1.49

0.48

1.49

3.21

0.930

0.41

17.5

225

1420

7.2

9.6

1.5

3600

749

54

8

361

44

3980

1100

20

9.2

6

1090

Ill

586

607

480

15

0-8

Bulk

D5-16A

7.90

6.97

1.1

17.1

1.05

3.34

0.41

11.2

2.94

0.282

0.06

0.04

2.10

9.90

59

267

1.7

2.1

2.7

5630

309

873

18

85

59

5

1520

80

4

19.9

<2

149

2.2

37.6

217

353

84

16

Mn

Sandstone

D7-11A

23.8

20.3

1.2

5.89

1.36

<0.01

0.67

1.24

2.83

0.752

0.46

0.20

8.70

16.6

222

1180

6.7

12.1

1.4

9310

2950

541

28

5

352

68

2900

1010

40

7.2

5

1150

31.1

80.7

568

505

578

16

0-5

Bulk

D8-1A

1.50

43.1

0.03

2.76

0.98

2.35

0.67

2.55

1.02

0.036

0.06

0.06

2.00

19.2

56

11520

0.6

<0.5

15.3

7160

889

1970

58

175

359

2

6280

54

11

3.7

<2

639

0.8

57.7

506

1610

25

18

Stratabound

Mn

D9-5-1A

19.9

20.9

0.9

6.40

1.29

1.28

0.60

1.16

2.81

0.895

0.45

0.19

10.2

16.9

222

1420

7.0

15.4

1.1

8400

3110

620

28

3

337

39

2570

1020

21

8.3

5

1140

34.0

86.9

523

493

504

9

0-5

Bulk

D9-6-1A

18.7

20.4

0.9

7.01

1.36

1.54

0.64

1.18

3.14

0.900

0.61

0.20

7.80

16.9

219

1300

6.8

14.1

0.9

7940

2480

507

40

5

277

37

3370

863

21

6.7

4

882

28.9

72.0

552

452

462

24

0-9

Bulk

All Ag contents <0.2ppm; Ge <10ppm; In <0.5ppm 

Duplicate analysis of sample

47
Table 23. Hygroscopic water-free (0% H2O~) composition of Fe-Mn crusts and 

stratabound Mn deposits from Table 22

Fe wt.%

Mn

Fe/Mn

Si

Na

Al

K

Mg

Ca

Ti

P

S

B ppm

Ba

Be

Bi

Cd

Cl

Co

Cu

Ga

Li

Mo

Nb

Ni

Pb

Rb

Sc

Sn

Sr

Te

Tl

V

Y

Zn

Zr

Hg ppb

Interval

Type

D5-2A

20.5

22.8

0.9

6.94

1.29

1.61

0.52

1.63

3.48

1.011

0.44

0.18

231

1538

6.7

12.0

2.0

9848

4009

827

55

9

394

48

3824

1170

21

11.7

7

1257

42.8

127

575

221

671

520

16

0-8

Bulk

D5-2A1

20.5

22.8

0.9

6.94

1.29

1.61

0.52

1.61

3.48

1.007

0.44

244

1538

7.8

10.4

1.6

3900

811

59

9

391

48

4312

1192

22

10.0

7

1181

~

120

635

208

658

520

16

0-8

Bulk

D5-16A

8.07

7.12

1.1

17.4

1.08

3.42

0.42

11.5

3.01

0.288

0.06

0.04

60

273

1.7

2.1

2.8

5751

316

892

18

87

60

5

1553

82

4

20.3

<2

152

2.2

38.4

222

25

361

86

16

Mn

Sandstone

D7-11A

26.0

22.2

1.2

6.45

1.49

<0.01

0.74

1.35

3.10

0.823

0.50

0.22

243

1292

7.3

13.3

1.5

10197

3231

593

31

5

386

74

3176

1106

44

7.9

5

1260

34.1

88.4

622

227

553

633

18

0-5

Bulk

D8-1A

1.53

44.0

0.03

2.81

1.00

2.40

0.69

2.60

1.04

0.037

0.06

0.06

57

11755

0.6

<0.5

15.6

7306

907

2010

59

179

366

2

6408

55

11

3.8

<2

652

0.8

58.9

516

10

1643

26

18

Stratabound

Mn

D9-5-1A

22.1

23.3

0.9

7.13

1.44

1.43

0.67

1.29

3.13

0.997

0.51

0.21

247

1581

7.8

17.1

1.2

9354

3463

690

31

3

375

43

2862

1136

23

9.2

6

1269

37.9

96.8

582

249

549

561

10

0-5

Bulk

D9-6-1A

20.3

22.2

0.9

7.61

1.47

1.67

0.69

1.28

3.40

0.977

0.66

0.22

238

1410

7.4

15.3

1.0

8612

2690

550

43

5

300

40

3655

936

23

7.3

4

957

31.3

78.1

599

249

490

501

26

0-9

Bulk

All Ag contents <0.2ppm; Ge<10ppm; In <0.5ppm 

Duplicate analysis of sample

48
Table 24. Statistics for 4 bulk Fe-Mn crusts from the Yap convergent margin hydrothermal leg 

KODOS 98-3 cruise; data from Table 23

Fe wt.%

Mn

Fe/Mn4

Si

Na

Al

K

Mg

Ca

Ti

P

S

H2CT

LOI

B ppm

Ba

Be

Bi

Cd

Cl

Co

Cu

Ga

Li

Mo

Nb

Ni

Pb

Rb

Sc

Sn

Sr

Te

Tl

V

Y

Zn

Zr

Hg ppb

Depth5

Thickness6

N

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

4

Mean

22.2

22.6

1.0

7.03

1.42

-1.18

0.65

1.39

3.28

0.952

0.53

0.21

8.60

16.9

240

1456

7.31

14.43

1.42

9503

3348

665

40

6

364

51

3379

1087

28

9.0

5

1186

36.5

98

595

237

566

554

17

2408

7

Median

20.5

22.2

0.9

6.94

1.44

-1.43

0.67

1.29

3.13

0.977

0.50

0.21

7.80

16.9

238

1410

7.34

13.25

1.22

9354

3231

593

31

5

375

43

3176

1106

23

7.9

5

1257

34.1

88

582

227

549

520

16

2504

5

SD1

10.2

10.1

1.0

3.17

0.64

0.86

0.30

0.64

1.48

0.432

0.25

0.09

3.97

7.6

107

661

3.29

6.74

0.73

4291

1570

316

21

3

167

27

1559

494

16

4.4

3

546

16.9

47

267

107

261

253

10

1099

4

Min'

20.3

22.2

0.9

6.45

1.29

<0.01

0.52

1.28

3.10

0.823

0.44

0.18

7.70

16.6

231

1292

6.72

12.03

0.98

8612

2690

550

31

3

300

40

2862

936

21

7.3

4

957

31.3

78

575

221

490

501

10

2029

5

MaxJ

26.0

23.3

1.1

7.61

1.49

1.67

0.74

1.63

3.48

1.011

0.66

0.22

10.2

17.2

247

1581

7.80

17.15

1.95

10197

4009

827

55

9

394

74

3824

1170

44

11.7

7

1269

42.8

127

622

249

671

633

26

2550

9

Standard deviation; Minimum; Maximum; Ratio of means, not a mean of the summation of 

ratios; Water depth in meters; Crust thickness in millimeters; LOI and H2O" from Table 22

49
160C 166

14C

REPUBLIC OF

JMARSHALL ISLAND

~ o~ « °~ u

172'

Figure 1. Atolls and seamounts comprising the Marshall Islands with the two boxed areas enclosing Lomilik Seamount and Litakpooki Ridge, which were studied during cruise KODOS 98-3; note the location of CTD 2 between Lomilik and Litakpooki seamounts. The boxed regions in the inset map show locations in Figures 1 and 4
160°30'E 160°35 'E 160°40'E 160°45 'E 160°50'E

&

o

o ' 

OO

o 

OO

o

(S

o 

OO

OO

o 

OO

Figure 2. SeaBeam bathymetry, dredge (D), CTD, and piston core (PC) locations for Litakpooki 

Ridge, located south of Ujlan Atoll in the Marshall Islands group; D14 and D15 from KODOS 97-4 

(Hein, Moon, et al., 1998); contour interval is 200m

51
161°20'E 161°25 'E 161°30'E 161°35 'E 161°40 'E 161°45 'E

Figure 3. SeaBeam bathymetry for Lomilik Seamount, located west of Anewetak Atoll; D4-D13 from KODOS 97-4 (Hein, Moon, et al., 1998); contour interval is 100m
136C 140

145 C

Figure 4. Atoll and island names within the Exclusive Economic Zone of the western Federated 

States of Micronesia, including the Yap convergent margin and the western edge of Caroline Ridge; hatchured lines are basins; boxed area was surveyed during KODOS 98-3; contour interval is 1000 m; modified from Chase et al. (1988).
137°30'E 137°45'E 138°00'E 138°15'E 138°30'E 138°45 'E

Yap Arc Yap Trench

00

§0

West Caroline Ridge

Figure 5. SeaBeam bathymetry, dredge (D), CTD, piston core (PC), box core (BC), and multiple core (MC) locations for Yap-Caroline Ridge convergent margin; contour interval is 200 m
100-,

I

u

1. 10 H

A.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

wrj 1"E,

0.1-

0.01

B.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Figure 6. REE plots of phosphatized limestone sample D1-10A, Litakpooki Ridge:

(A) Chondrite (Anders and Grevesse, 1989) normalized, and (B) Post Archean Australian

Shale (PAAS, McLennan, 1989) normalized

55
A. (Co+Ni+Cu)xlO

 Bulk crusts, Litakpooki Ridge < 60 mm 

o Bulk crusts, Litakpooki Ridge > 60 mm

 Bulk crusts, Yap Arc

+ Bulk crusts, SW Caroline Ridge

 Stratabound Mn, Yap Arc 

Mn-cemented SS, Yap Arc

Fe Mn

B.

(Co+Ni+Cu)xlO

 Non-phosphatized crust layers (P < 1%) 

o Phosphatized crust layers (P > 1%)

Fe Mn

Figure 7. Mn-Fe-(Co+Ni+Cu)xlO ternary diagram after Bonatti et al. (1972) for: 

(A) bulk crusts, and (B) crust layers

56
i

looo100-

10-

A.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

lOOn

10-

B.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Figure 8. Range of REE plots for 13 Fe-Mn samples from Litakpooki Ridge: 

(A) Chondrite normalized, and (B) PAAS normalized

57
1000-

I I

100-

10-

A.

I I I I I I I I I I I I V I

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

lOO-i

on

"cL 10-

c/3

B.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Figure 9. REE plots of bulk crusts and layers from dredge Dl, Litakpooki Ridge: 

(A) Chondrite normalized, and (B) PAAS normalized

58
1000-

I

C/3

C/3

|

"a.

C/3

100-

10-

D2-2A 

D2-2B 

D2-2C 

D2-2D 

D2-3A 

D2-6A 

D2-1C*

A.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

lOO-i

10-

D2-2A 

D2-2B 

D2-2C 

D2-2D 

D2-3A 

D2-6A 

D2-1C*

B.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Figure 10. REE plots of bulk crusts and layers from dredge D2, Litakpooki Ridge: 

(A) Chondrite normalized, and (B) PAAS normalized

59
Factor 1: CFA phase 

38.6% of sample variance

0.1

-0.1

-0.2

-0.3

0.5

0.4

0.3

o

I 0.2

-o.i

-0.2

Al

K Si

ON

O

0.8

fi 

o 

o 

on

i_i

1 0.6

UH

0.4

0.2

Factor 3: Residual biogenic phase 

13.6% of sample variance

0.4

0.3

0.2

0.1

-0.1

-0.2

-0.3

-0.4

nun 

iniiii

Tl Co Ni Ga Mn Pb 

Figure 11. Four Q-mode factors for 9 bulk crusts from Litakpooki Ridge. The four factors account for 98

Factor scores between 0 and 10.141 are not included because random noise makes it difficult to resolve the 

factor to within 10° of an absolute direction in variable space.
~ 0.1

-0.1

-0.2

-0.3

0.7

0.6

2 0.5

Factor 1: Aluminosilicate phase 

39.6% of sample variance

0.4

0.2

0.1

w Factor 2: Mixed 6 MnO2 and residual biogenic phases 

29.9% of sample variance

Zn Mn Cu

III III 11II11

1

I

XI 

03

'C!

Factor 3: CFA-diagenetic phase 

29.9% of sample variance

Ca Co Nb Pb Ti Bi

-0.1

-0.2

-0.3

Figure 12. Three Q-mode factors for 5 bulk crusts >85mm from Litakpooki Ridge. The three factors account for 99.4% of 

the variance. Factor scores between 0 and 10.141 are not included because random noise makes it difficult to resolve the 

orientation of the factor to within 10° of an absolute direction in variable space.

61
lOOOn

I 

o

3 100-

10-

lOOn

10-

D5-2A

D7-11A 

D9-5-1A

A.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

D5-2A

D7-11A

D9-5-1A

B.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Figure 13. REE plots of bulk crusts from dredges D5, D7, and D9, FSM: (A) Chondrite 

normalized, and (B) PAAS normalized

62
looc 

o

JG

y

0>

10--

A.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

10-r

0.1--

0.01

D5-16A 

D8-1A

B.

La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Figure 14. REE plots of hydrothermal Mn-cemented sandstone (D5) and stratabound 

Mn layer (D8) from Yap Arc: (A) Chondrite normalized, and (B) PAAS normalized

63